Why Track Timestamps in GA4?

Timestamps are invaluable for:

• Pinpointing when users interact with your site.

• Analyzing user behavior during specific campaigns or external events.

• Syncing analytics with other tools like CRMs or dashboards for deeper insights.

Step 1: Set Up GA4 and Google Tag Manager

Before starting, ensure your GA4 property is linked to your site, and GTM is installed. You’ll also need a GA4 Configuration Tag with your Measurement ID.

Step 2: Add a Timestamp Parameter in GTM

To track timestamps, create a custom JavaScript variable in GTM and pass it to your GA4 event tags.

1. Create a Timestamp Variable:

   • In GTM, go to Variables > New > Custom JavaScript.

   • Add this script to format timestamps as yyyy-MM-dd HH:mm:ss:

       function() {
         var date = new Date();
         var yyyy = date.getFullYear();
         var MM = String(date.getMonth() + 1).padStart(2, '0');
         var dd = String(date.getDate()).padStart(2, '0');
         var HH = String(date.getHours()).padStart(2, '0');
         var mm = String(date.getMinutes()).padStart(2, '0');
         var ss = String(date.getSeconds()).padStart(2, '0');
         return yyyy + '-' + MM + '-' + dd + ' ' + HH + ':' + mm + ':' + ss;
       }
     

   • Save the variable as Formatted Timestamp.

2. Add the Timestamp Parameter to Your GA4 Event Tag:

   • If you don't already have a GA4 Event Tag, create one:

     1. In GTM, click New Tag and select Google Analytics: GA4 Event.

     2. Enter an event name (e.g., page_view) and associate it with your GA4 Configuration Tag.

   • Open the Event Tag and scroll to Event Parameters.

   • Click Add Row:

     • Parameter Name: timestamp

     • Value: {{Formatted Timestamp}}

   • Save and publish your GTM container.

Step 3: Verify Timestamp Data in GA4

To confirm the setup works, use DebugView in GA4 or Preview in GTM.

1. Enable GTM Debug Mode:

   • Preview your GTM setup or append ?debug_mode=1 to your site’s URL.

2. Check DebugView:

   • Go to Admin > DebugView in GA4.

   • Trigger events (e.g., page views) on your site.

   • Verify that the timestamp parameter appears for your events.

Step 4: Create a Custom Dimension for Timestamps

GA4 requires you to register timestamp as a custom dimension to use it in reports.

1. Go to Admin > Custom Definitions in GA4.

2. Click Create Custom Dimension.

3. Fill in the details:

   • Dimension Name: Timestamp

   • Scope: Event

   • Event Parameter: timestamp

4. Save the dimension.

Note: Custom dimensions only start collecting data after creation; past data won’t be included.

Step 5: Use Timestamp Data in Explorations

Once data propagates (24-48 hours), use Explorations to analyze timestamps.

1. Create an Exploration:

   • Go to Explore in GA4 and start a Free Form Exploration.

   • Add Timestamp as a Dimension.

   • Add metrics like Event Count.

2. Visualize Data:

   • Filter by specific events (e.g., page_view).

   • Use tables or charts to see timestamped activity.

Common Troubleshooting Tips

1. Timestamp Not Showing in DebugView:

   • Ensure the Formatted Timestamp variable is added correctly to your GA4 Event Tag.

2. Timestamp Missing in Reports:

   • Verify the custom dimension setup in GA4.

   • Wait 24-48 hours for data to propagate.

3. DebugView Works, but Explorations Don’t:

   • Confirm that the timestamp dimension is included in your Exploration setup.

Why Use GA4 + GTM for Timestamps?

This setup combines GA4’s powerful analytics with GTM’s flexibility, offering:

• Precise tracking of user behavior.

• Easy integration with other tools.

• Cost-effective solutions using free tools.

Bonus: Push Timestamp Data to Google Sheets in Real Time

If you want to avoid waiting next data for data to appear in GA4 reports and push timestamp data directly to a Google Sheet in real time, follow these steps:

1. Create a Google Sheets Document

1. Open Google Sheets and create a new spreadsheet.

2. Add headers in the first row, such as:

    Timestamp | Page URL
   

2. Set Up a Webhook with Google Apps Script

1. Open Extensions > Apps Script in the spreadsheet.

2. Replace the default code with:

    function doPost(e) {
      var sheet = SpreadsheetApp.getActiveSpreadsheet().getActiveSheet();
      var params = JSON.parse(e.postData.contents);
      sheet.appendRow([params.timestamp, params.page]);
      return ContentService.createTextOutput(JSON.stringify({status: 'success'}))
          .setMimeType(ContentService.MimeType.JSON);
    }
   

3. Deploy the script as a Web App:

   • Execute as: Me

   • Who has access: Anyone

4. Copy the Web App URL.

3. Update GTM to Push Data

1. Create a Custom HTML Tag in GTM:

    <script>
      var payload = {
        page: document.location.href,
        timestamp: new Date().toISOString()
      };
      fetch('YOUR_WEB_APP_URL', {
        method: 'POST',
        mode: 'no-cors',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify(payload)
      });
    </script>
   

2. Replace YOUR_WEB_APP_URL with the URL from your Apps Script deployment.

3. Attach a trigger (e.g., All Pages) to fire the tag.

4. Test the Setup

1. Use GTM Preview Mode to ensure the tag fires correctly.

2. Verify that data appears in your Google Sheet.

Conclusion

With a few simple steps, you can add timestamps to your GA4 analytics and even push this data to Google Sheets in real time. This guide helps you set up, test, and enhance your analytics seamlessly—ensuring your data is actionable and valuable.

Have questions or tips? Let me know in the comments!

Conclusion

With a few simple steps, you can add timestamps to your GA4 analytics and unlock deeper insights into user behavior. This guide helps you set up, test, and report timestamps seamlessly—ensuring your analytics are more actionable than ever.

Have questions or tips? Let me know in the comments!

Remember that no matter how trustworthy the company is, you should keep your crypto in your own wallets, where you are the only one who owns the private key.

Introduction to How Bitcoin Wallets Work

Before we learn about various types of wallets, let’s figure out the basics. There are four types of bitcoin wallets I will be reviewing in this guide:

• Hardware wallets (physical offline device)

• Desktop wallets (online or offline software)

• Mobile wallets (mobile apps)

• Web wallets (online software)

There are different types of them, but they all have three things in common, which are required by the bitcoin blockchain to operate:

1. Seed phrase (secret)

2. Private key (secret)

3. Public key (public)

The seed phrase and a private key are made to keep your wallet and funds secured. If you keep these pieces of information responsibly, your wallet will be safer than your bank account. The public key is your wallet address to share with others to receive bitcoin or another cryptocurrency, which will be your “account number”. Let’s dive a little bit deeper into each of them.

What is a Seed Phrase In Crypto Wallet?

The Seed Phrase is the string of 12 to 24 random words generated by your wallet automatically when you create it, so you can write down the phrase and store it safely. If you lose the private key, you can restore wallet access using the seed phrase.

Here is what it looks like in different wallets:

Desktop wallet seed phrase example

Hardware (Trezor One) wallet seed phrase example

What is Bitcoin Private Key?

A private key is a secret, alphanumeric password/number used to spend/send your bitcoins to another Bitcoin address. It is a 256-bit long number that is picked randomly as soon as you make a wallet.

The degree of randomness and uniqueness is well defined by cryptographic functions for security purposes.

This is how a Bitcoin private key looks:

5Kb8kLf9zgWQnogidDA76MzPL6TsZZY36hWXMssSzNydYXYB9KF

To keep your wallet safe, the Private Key and a Seed Phrase should not be shared with anyone and stored safely.

What is a Public Key (address)?

This is another alphanumeric address/number which is derived from the private key only by using cryptographic math functions.

It is impossible to reverse engineer it and reach the private key from which it was generated.

This is the address used to receive bitcoins publicly.

Here is how the Bitcoin public address looks:

1EHNa6Q4Jz2uvNExL497mE43ikXhwF6kZm

This address is always seen and broadcasted for receiving bitcoins. Users can make as many public addresses as they want to receive bitcoins. One wallet can have many public addresses.

Great, now you know the basics of the basics! Wasn’t that hard, right? Let’s proceed to learn more about the types of wallets.

Custodial and Non-Custodial Wallets

• A custodial wallet is a type of wallet that is managed and stored by a third-party service provider. It requires users to give up control of their private key, which grants them access to their funds.

• On the other hand, a non-custodial wallet gives users full control of their private keys, allowing them to manage and store their own crypto assets.

Custodial wallets are easy to use but come with some security risks, while non-custodial wallets offer more security but require more technical knowledge. Hardware wallets are the most secure type of wallet available for storing crypto assets; these are cold wallets that are not connected to the internet and provide an extra layer of protection against hackers and malicious actors. On the other hand, hot wallets are connected to the internet and can be used instantly for transactions but they also have a higher risk associated with them. Whether you need a custodial or non-custodial wallet or a hardware or hot wallet will depend on your unique situation and needs when managing your cryptocurrency.

Hardware Type of Crypto Wallets

A hardware wallet (cold wallets) is a physical type of storage of your private key. The wallet looks like a flash drive that stores the critical wallet.dat file internally, which means that under no circumstances the private key leaves the device.

The most popular and at the same time affordable and reliable hardware wallets are Ledger Nano S and Trezor One. They both support more than 1,000 cryptocurrencies and tokens. Hardware wallets are the most reliable way of long-term storage of cryptocurrencies since hacking is impossible because the wallet is not connected to the Internet. You can put such a wallet in your pocket, or better yet, hide and keep it in a safe place at home.

Comparison of the most popular hardware wallets.

Desktop Cryptocurrency Wallets (online or offline software)

Desktop Wallets (hot wallets) include software wallets that must be installed on a computer. These wallets are divided into full-fledged (Bitcoin-Core, Armory) and lightweight (Electrum and Bither). The first subset of wallets involves downloading the complete Bitcoin blockchain. Electrum and Bither use partial synchronization, which only takes up a few megabytes.

The most reliable option is Bitcoin Core. This wallet is fully synchronized with the blockchain. This means you must download the entire blockchain, which is at least 145 GB and growing. If you are not ready to download such an array of data to your computer, use the lightweight versions of wallets.

Comparison of the most popular desktop wallets.

All software is free. Download the installation file, configure the settings, and wait for the installation to complete.

Mobile Wallets (mobile apps)

The fourth category is mobile wallets. Typically, these are desktop (computer) version alternatives made for mobile devices. Due to limitations in physical memory, they cannot load the entire blockchain. The mobile version of Bitcoin Core is called Bitcoin Wallet. There are programs for all popular platforms (Android, iOS, Windows Phone, Blackberry). If you decide to go this way, we recommend the BRD wallet (link for iOS | link for Android).

Comparison of the most popular iOS mobile wallets (Apple devices).

Comparison of the most popular Android mobile wallets.

Web Wallets (online software)

As it stands from its name, web wallets are developed on websites accessed from your web browser. By this, to use such wallets, you do not need to download or install anything on your computer. They work entirely online.

This is a very convenient way because you don’t have to worry about carrying the hardware wallet with you whenever you want to make a transaction or be afraid if you lose your mobile device with a wallet installed. However, you must consider that if something goes online - it is subject to a hacker attack. We use the web to browse many websites and do not always check them for safety, so one wrong link click can potentially cause the loss of funds. We don’t suggest using this type of wallet for your cryptocurrency long-term savings purposes. On the other hand, always ask yourself, if you were the owner of a website providing wallets to consumers, wouldn’t you have the desire to steal the funds? It is quite possible with cryptocurrencies since they are anonymous and give privacy to their users.

Note that we are talking about Bitcoin wallets in this course. Many more different wallets were developed for multiple coins (including Bitcoin) and created solely for other cryptocurrencies.

Let’s jump straight into practice, where you will set up your own crypto wallet!

How to Create a Bitcoin Wallet

This section will teach you the three most popular ways to create your cryptocurrency wallet. My strong suggestion goes to the hardware wallet due to its security features. If you still want to try other types, start with desktop or mobile wallets.

• Hardware Wallets

You can store your bitcoins on this device. This option is also called “cold storage”. As mentioned above, the Ledger Nano S and Trezor One are the most affordable devices. These wallets are generally considered the best crypto wallets by most people. You can order free express delivery of the product anywhere in the world.

Suppose you used or will be using Coinbase for purchasing cryptocurrencies. In that case, keeping it there while you wait for your hardware wallet delivery is safe. However, if you can’t wait to create your wallet and transfer funds, you can use any of the options below.

The device will arrive packed with all the necessary parts and information about the setup. We won’t publish the setup instruction for hardware wallets in this course to avoid misinterpretations, which can lead to risk exposure. Please, read the included user manual carefully and follow the instructions as it suggests. The process is beginner-friendly and straightforward, and many compare it to the setup of a new iPhone.

• Desktop wallet installation

Let’s finally get to practice and install a lightweight wallet Electrum on your computer. We will show the step-by-step instructions for Windows installation.

• Open the Electrum website and choose your operating system: (1) for Windows (2) for Mac (Apple computers). If your browser says that the file can harm your computer, ignore this message and keep the file.

  

• After downloading, open the downloaded file and allow the app to make changes on your computer. Follow the installation steps. Now run the Electrum App from your desktop. Note: if you have an antivirus, it might give a notification like the one below, cancel or ignore it.

• Choose “Auto Connect” and click “Next”.

• Now you can give a name to your wallet (optional). Then click “Next”.

• The installation wizard will then ask to choose the wallet type. Choose “Standard wallet”.

• Choose “Create a new seed” on the next step of installation.

• The next step is to choose a Seed type. Click “Legacy”.

• The next step is critical for the safety of your wallet. Write down the seed phrase on a piece of paper in the order it is displayed (paper wallet). Make multiple copies of the seed phrase and keep it in different safe places. Read the WARNING carefully!

• Tip: I recommend using your own simple encryption method to increase security. Do you have a favorite number? Let’s say “3”. Just shift letters to 3 steps forward or backward to encrypt all words according to the alphabet. Here is an example:

• Then you need to come up with a password for your wallet. You can leave it without a password if you think your storage method is bulletproof, but it is never too little to keep your money safe. Go ahead and create one:

• All set! Now you can receive and send bitcoins using the Electrum wallet on your computer! The tab “Receive” contains your receiving address (public key) and a QR code.

• -If you want to send bitcoins to your other wallet or someone else, use the tab “Send”. Insert the receiving address (public key) into the “Pay to” field and specify the amount you want to send. You can adjust the amount of fees you wish to pay, influencing the speed your transaction will go through.

Reminder: Do not give your password, private key, or seed phrase to anyone. Do not store them on e-mail or other online software.

• Mobile wallet installation

In this section, you will learn the installation of the BRD wallet, as one of the most stable and safe mobile wallets for Android and iOS devices. This will be a new wallet (with a new Seed Phrase and Private Key), not a copy of the one you created with Electrum. Let’s take a step-by-step look at creating an iOS wallet similar to Android. Installation is as simple as possible and takes no more than 2 minutes.

• First, download the wallet (link for iOS / link for Android) and run the application. In the window that appears, click “Get started”. The app will show you its features and suggest to “Buy some coin”. For this manual, we will ignore this and tap on “I’ll browse first”. Good to know. Suppose you start using your wallet created in Electrum or any other place where you own the private key. In that case, you can tap “Restore wallet” and have a copy of it in your BRD wallet on your mobile device.

• Now you need to come up with a PIN you will use to unlock the app and authorize transactions.

• Next, the message will appear with words that will help to restore the wallet in case of loss of access. These random words are called a Seed Phrase. As we covered in the introduction to this mini-course, the seed phrase is your only chance to restore access to the wallet if you lose your private key. In the case of mobile wallets, if you accidentally delete the wallet app, lose data when switching to a new phone, or lose your phone. Tap “Continue” and take this step seriously! Write down all the words on the encrypted paper as described in the previous section about the Electrum wallet.

• You need to confirm your recovery key (seed phrase) by typing in the requested words in the order it was written down. In our case, the app asked for words #4 and #6.

• All set. The wallet is ready. Tap “Go to Wallet” on the next step. Compared to the desktop wallet, where you can create the wallet only for Bitcoin, the app will create multiple wallets (Bitcoin, Ethereum, and BRD Token). BRD is a cryptocurrency of wallet developers. Feel free to enable Face ID, but remember the wallet PIN code (six digits) you entered initially. After a certain period of using the Face ID, the app will prompt you to enter the PIN code again.

• If you want to send or receive any coin from your wallet, choose it from the list and tap “Send” or “Receive”. To receive it, copy your address right under the QR code or scan the QR code from another device with a mobile wallet. This is your address to insert in the “To” field on the exchange or in another wallet.

Now you can easily send and receive bitcoin to your account. In my humble opinion, this is the best bitcoin wallet for mobile devices. The question “how to use it” will not be a problem because it is perfect for beginners and has an intuitive interface.

Summary

There are various types of wallets depending on your preferences. They have pros and cons, but security is the first thing you must look at before choosing a bitcoin wallet. Is a wallet developer trustworthy? You will never make a mistake by choosing the one with an open-source code, which means they published the code of the wallet to the public, and everyone can review it.

If there were only two takeaways from this post, they would be the following.

1. The first question you have to ask is whether you own the private key. If not, don’t use that wallet.

2. The second question is, “Am I the only one with access to the private key? Can wallet developers also have access to it? Remember, your funds are at risk if you don’t own the private key with a seed phrase or if someone else has access. Always take this seriously. You are your bank now.

Money is also on the Internet now. We have online banking and debit/credit cards to use our digital money. The bottleneck within the current approach to money is the bank itself. Websites and mobile apps are just gateways to your bank account, and a bank is an intermediary that controls your account and money.

In contrast to banks and fiat currencies, Bitcoin gives its users complete control and full ownership of the account (wallet) and money (bitcoins). Your account doesn't need government insurance if it goes bankrupt, as any bank does. You, as a user, don't have any limitations on how you use your money. No matter who you are, where you come from, or how rich you are, everyone is equal and can benefit from all features.

Understanding Bitcoin

What is Bitcoin?

Bitcoin (abbreviated as BTC) is a digital payment system in which virtual "money" (bitcoins) circulates. Do you have a VISA or Mastercard plastic card? Both Visa and Mastercard are also electronic payment systems. However, they use our regular currency – dollars, euros, etc., and all transactions go through bank processing. Such currencies are called fiat. The Bitcoin system uses cryptocurrency – a purely digital currency that is not linked to any world bank or the economy of any country. It has its value, which is directly dependent on demand.

Let's compare three types of money and their traits: Bitcoin, Gold, and Fiat.

You can see Bitcoin outperforming gold and fiat money. As we advance, you will strengthen your knowledge about Bitcoin's traits and why it is setting new standards for how we use and understand money.

Critical features of Bitcoin. Why do we need it?

• Permissionless. You don't have to ask anybody to use cryptocurrency. It's just a software that anybody can download for free. After you install it, you can receive and send Bitcoin or another cryptocurrency. You can even create your own currency. No one can prevent you. There is no gatekeeper.

• The whole system is decentralized. No bank, agency, or government entity regulates Bitcoin. All network members are equal regardless of nationality or other characteristics. For example, in Visa and Mastercard, there are Gold, Platinum, or VIP cards. There are restrictions on the size of transactions that differ between members. But with Bitcoin, everyone is equal, and there are no limits.

• Anonymity. When transferring the BTC, participants do not disclose their identities. For transactions, a bitcoin address (a hash with 27-34 characters) is used without disclosing other data about the recipient or sender. Remember the transfers between bank accounts or other electronic systems? Submitting a sender and receiver name, address, ID, and verified bank account number is required.

• Irreversibility. All operations in Bitcoin are irreversible. They cannot be undone, stopped, or blocked. Theoretically, a complete rollback of the system (blockchain) is possible. Practically, it is impossible, being extremely difficult and costly to do.

• Security. Bitcoin uses the SHA-256 encryption, so hacking a Bitcoin wallet is impossible. All data is stored in a particular file, access to which only you have. It is also impossible to "intercept" data during a transaction, as in the case of the banking system. Bitcoin uses cryptographic records – encrypted data that guarantees confidentiality and security. The only chance to steal your wallet data is if you don't store it securely - human factor (or social engineering), which has nothing to do with the Bitcoin network.

• The direct nature of operations. In Bitcoin, transfers are made directly between participants – the P2P (peer-to-peer) principle is used. A transaction occurs without the participation of a third party like a bank, a processing center, or a server. Therefore, the operation in Bitcoin can't be tracked by anyone except its participants. By "can't be tracked", we mean that no one can influence or manipulate the transaction. Otherwise, all transactions are public, and anyone can go and check the record of every Bitcoin transaction, even the very first one.

History of Bitcoin Explained

The history of cryptocurrency has a vague chronology. For decades, cryptographers have worked to create a unique decentralized system, the work of which is based on mathematical calculations. Using their predecessors' experience and expertise, in 2008, Satoshi Nakamoto and Hal Finney created the world's first cryptography-based form of digital currency, or simply electronic money – Bitcoin. Nakamoto received the primary glory – they published a file with the Bitcoin protocol and briefly described the features of the new payment system. The smallest fractional part of the coin is named in his honor – 0.00000001 BTC, or simply one satoshi. In other words, one bitcoin is 100,000,000 Satoshi.

Why was bitcoin created? The reasons for the development of the field of cryptocurrencies are revealed by their features: anonymity, decentralization, security, and general accessibility. Ideally, the Bitcoin ecosystem should guarantee fast transactions without the participation of a third party (bank, payment processor, government) and with a high level of security.

An interesting point of view was expressed by the famous Russian businessman Sergey Mavrodi back in 2013:

"All this hype around cryptocurrencies is associated with its anonymity. People are tired of Big Brother watching their every action. Everyone is tired of this. And bitcoin, in this regard, is a breath of fresh air."

This quote answers the question of why bitcoins are needed. Transaction privacy is a crucial feature of cryptocurrencies.

How Bitcoin Works (for beginners)

The entire Bitcoin ecosystem rests on the blockchain. A blockchain is generally a time-stamped series of immutable data records managed by a cluster of computers not owned by any single entity. Each of these data blocks (i.e., a block) is secured and bound to each other using cryptographic principles (i.e., chain).

🤔 There should be a better way to explain this, right? Now, let's decipher it in simple words.

1. Imagine that each transfer (transaction) in Bitcoin is recorded on a separate page, a simple piece of paper (aka public ledger). The sequence of multiple pages forms the chapter of the book – a block.

2. To record a new page (conduct a new transaction), we need to "turn over" all the previous pages and chapters. This means that each new transaction is carried out in a chain – with the processing of old blocks (turning previous pages and chapters). A new book chapter can only begin after the old one is finished. And all the chapters form the book, and the blocks are the blockchain. Pages and chapters cannot be removed or edited. And access to the Bitcoin blockchain is open to all participants in the system.

3. Every participant (node/computer) has a copy of the book, which is always in sync with others. Suppose someone tries to change the information on previous pages, for example, to add illegal bitcoins to their wallet. In that case, other participants will notice that and compare it to copies of other participants. It will be rejected if the information doesn't match the previous records. This process happens automatically, and there is no need to do such checks manually.

Blockchain is an extensive open database in which encrypted information about all completed transactions is stored. As said before, every computer participating in the network has a full copy of the blockchain (book), constantly updating as new transactions and blocks appear.

Here are some other differences between "virtual" bitcoin and regular money:

• The form. Bitcoin is a currency that does not have a physical appearance. There are physical "paper wallets" with a QR code or wallets in the form of coins where BTC is stored. However, BTC cannot call them money in the truest sense. We can say that Bitcoin is a set of numbers generated by an algorithm. Not a paper note or a metal coin.

• Value. The fiat currency exchange rate directly depends on the economic and political development of the country or confederation to which it is attached. Currencies in more than 100 countries are tied to the US dollar. The cost of bitcoin is determined by demand. It does not directly depend on economic processes (although it is indirectly linked).

• Emission. Theoretically, fiat money does not have emission limits. They can be printed as many as Federal Reserve, or Central Bank wants. BTC has its own preprogrammed limit embedded in the system - 21 million coins (20,999,999, 9,769 coins, to be precise). According to forecasts, Bitcoin will reach this figure in the middle of the 22nd century. The only way of emission is mining, so the estimates are based on the mining difficulty and miner reward size. Difficulty increases or decreases with the number of competition among bitcoin miners. The more miners, the harder it is to mine new bitcoins. Miner reward size is a preprogrammed reward for the job they do, which is split in half every four years. Miner's reward is the only way to bitcoin emission. No one can change the size of the reward or issue more coins at will.

• Direct transactions. Even if we are talking about the electronic version of ordinary money (card, wallet), transactions are performed with the participation of a third party. In Bitcoin, the operation is direct (P2P).

BTC is more complex to evaluate than other common types of assets. Some features of bitcoin can be attributed to its advantages and its disadvantages. Let's take a look at the element of the irreversibility of transactions. On the one hand, you will receive the cryptocurrency you are sent – no system failure will block the transaction. On the other hand, this is a feature of Bitcoin that scammers or black market representatives exploit.

You might often hear that the speed of settlement of transactions is an advantage of Bitcoin. A transaction can take 10-20 minutes, sometimes an hour to settle. To complete it, you need 6 confirmations of other participants (nodes), which happen automatically. With a high network load of transactions, transfers settlement slows down because nodes need more time to confirm transactions. Another drawback is the regulatory activity of the authorities of different countries concerning cryptocurrencies. Formally, BTC creates the same conditions for all potential network participants. However, cryptocurrencies are banned in some countries (Vietnam, India, Ecuador, and partly China).

Some other disadvantages:

• Unstable price: The potential of BTC as a payment option decreases due to high bitcoin's price volatility.

• Fraud. Bitcoin itself is very secure and reliable. However, inexperienced people may fall for scam schemes: fake exchanges, fraudulent investment projects, viruses, social engineering, etc.

Where to Mine, Earn, or Buy Bitcoins

Like most other cryptocurrencies available, Bitcoin is generated through the use of the hardware power of computers (processors and video cards). This process is called Bitcoin mining. If in 2009-2010. To extract bitcoins, you could use a regular computer. To do so, you need powerful hardware rigs – mining farms. These farms combine dozens, sometimes hundreds, of video cards or particular processors such as ASIC miners. This wasn't always like that. In the early years of Bitcoin network development, you could mine tens and even hundreds of bitcoin on a regular home computer.

This equipment costs thousands of dollars and requires additional care and technical skills. For beginners, this method of obtaining BTC is not recommended. And in some countries, mining is wholly prohibited.

Here are other ways to get bitcoin:

• Centralized Exchanges (CEX). There are dozens of online exchanges selling cryptocurrency for fiat. Most offer multiple currencies for sale, and if it is a cryptocurrency exchange, you will definitely be able to buy and sell bitcoin. Such exchanges have a simple and easy-to-use interface, similar to regular online stores. The most popular ones are Binance and Coinbase.

• Decentralized Exchanges (DEX). These are the platforms with more sophisticated interfaces primarily designed for crypto-crypto trading. However, they also offer purchasing of Bitcoin and other cryptocurrencies with a debit card or directly from a bank account. The most popular are dYdX and Uniswap.

• Bitcoin faucets. These are services that distribute cryptocurrency to visitors for free. Hold on, though, don't run out right away to get free Bitcoin! There is nothing truly free in this world. You need to fill in the captcha or perform another task to get a small amount of BTC. There are hundreds of them online. The amount you can earn per task is tiny. I used one faucet and could receive only 0.00000027 BTC per hour, around $0.002.

• BTM or Bitcoin ATM. You can buy Bitcoin through a specialized Bitcoin ATM by inserting cash into the machine. However, this method is the most expensive because BTM operators charge high fees, or the price is 7-10% above the market price.

What can be bought with bitcoin?

In cryptocurrency's early years, all transactions were conducted "informally". Buyers and sellers chatted in chat rooms (mIRC, Miranda), social networks, and forums. The most famous purchase of goods for bitcoin happened on the Internet forums. It is considered the first purchase of anything for cryptocurrency.

A user with the nickname Laszlo created a topic on the BitcoinTalk forum on May 18, 2010, titled "Pizza for bitcoins?". He asked who could order two pizzas for him for 10,000 BTC.

At the time, it was the equivalent of $30. One user agreed to the offer and ordered Laszlo a pizza, completing the first and most famous purchase using BTC.

Only a little time has passed since that moment, but BTC as a payment option has developed globally. In the summer of 2017, it became known that 260,000 retail stores in Japan would start to accept Bitcoin as payment. This is an essential step toward the globalization of payments in BTC. Nowadays, more and more car dealers, real estate agencies, jewelers, restaurants, bars, flight and hotel reservation platforms, and simple convenience stores are accepting Bitcoin as a payment option. It's hard to believe, but even some universities accept cryptocurrency payments for education.

Moreover, there are cryptocurrencies, like Dash, whose developers are creating an infrastructure for "unbanked" regions of our world. Their goal is to use and accept cryptocurrency as an everyday payment method for goods and services exchange. Every month, we read news about a new coffee shop, bar, or restaurant starting to accept cryptocurrency payments worldwide. In some countries, taxi drivers use bitcoin. In the United States, Republican Party supporters can donate money for its development in BTC. Cryptocurrency even got to space. Virgin Galactic, a space travel company, uses it.

Common crypto and blockchain myths

Crypto and blockchain are topics that have seen a lot of hype in recent years. However, there are still a lot of misconceptions out there about both crypto and blockchain.

❌ One of the most common myths is that crypto and blockchain are synonymous terms when they are separate technologies. Crypto refers to digital currencies such as Bitcoin, while blockchain is the technology behind them.

❌ Another common crypto and blockchain myth is that they are only used for illegal activities such as money laundering or drug trafficking. This simply isn’t true – crypto and blockchain are used for many legitimate purposes, such as banking and trading. Another myth is that cryptocurrency is completely anonymous when all transactions can be tracked on the public ledger.

❌ Finally, some believe blockchain technology is only useful for financial transactions when it has also been applied to other industries, such as healthcare and logistics. Although these myths can seem convincing at first, it’s important to remember that they are nothing more than misunderstandings of how crypto and blockchain work.

Summary

Bitcoin is the Internet of Money, developed by Satoshi Nakamoto in 2008 and launched in 2009. It is a decentralized and anonymous platform for cheap and fast value transactions worldwide, available for everyone with computer or mobile device access. No registrations, qualifications, personal information, or proof of income is required to start benefiting from Bitcoin.

It is not backed by any type of asset or economy as fiat currencies are, so it is volatile. It is independent of external factors, gold mining volumes, a country's economic collapse, or poor monetary policy.

Bitcoin emission is limited to 21 million BTC, which will be reached in the 2100s.

The Bitcoin network has never been hacked or compromised since its very beginning.

This leads us to the conclusion that cryptocurrency is the most advanced payment system available now, one that can be used anywhere in the world and for any purpose, with literally no limitations. Anyone can make a payment gateway within minutes for any project. By anyone, I literally mean anyone, from the poorest and most undeveloped regions of the world up to the space station inhabitants. The only requirement to start accepting bitcoins to sell goods and services is a desktop or mobile device connected to the Internet. How cool is that?

Keep exploring

1. Head over to the Bitcoin page on CoinMarketCap and learn more about:

   • Price history (chart in the middle of the page)

   • Ratings

2. Visit the blockchain explorer to see all bitcoin transactions and other interesting information in real-time such as:

   • Average transaction fee

   • Average amount of BTC per transaction

   • Number of transactions per day

This is a first post in a series of educational posts about cryptocurrencies and web3 space. Subscribe to my newsletter above to receive a notification about new releases in this series.

Why would anyone need to create a cryptocurrency? The answer remains open, partly due to the characteristics of cryptocurrency. Previously, there was no convenient and quick way to make anonymous digital payments with a high level of security. Since Bitcoin, the first cryptocurrency, was created, this isn't an issue anymore.

In a series of DeFi basics articles, me and you, dear future crypto punk, will finally connect the dots on what and why crypto, and discover a new wild west of financial freedom, crypto hacks, anonymous mumbo jumbo, and maybe a few conspiracy theories. This is another set of words put together to educate the uneducated on the essence of crypto, how to use it, how not to lose a house chasing fantasy profits, and how not to get rekt by:

• cryptocurrency scams, such as sending your money to fake Elon Mask to get 2x back,

• getting your funds locked and hijacked on exchanges,

• exposing your crypto wallet secrets to thieves,

• and many more in between.

Some of the info will be a little academic, some conspiratorial, but none will be intentionally misleading. I have a background in economics, marketing, business, and programming. Therefore, I hope this experience will allow me to use better sets of words to assist you in understanding why so many people, including me, invest in cryptocurrency and blockchain technology as a whole.

2009 is considered the official cryptocurrency year of birth when the Bitcoin network began its operation. Satoshi Nakamoto, a mythological character or group of people who are still unknown, is considered the creator of Bitcoin and other cryptographic currencies. The Bitcoin protocol was first published on Satoshi Nakamoto's behalf. Satoshi also initiated the first transaction in the genesis block.

Satoshi Nakamoto has many years of experience in cryptography and IT technologies, which was implemented into the Bitcoin infrastructure. The number of years of development and the research conducted has yet to be discovered precisely.

The term "cryptocurrency" was first used in a Forbes article about Bitcoin in 2011. Forbes readers and fans of the new virtual currency liked the name so much that it soon began to characterize the whole industry.

Cryptocurrency Explained

Cryptocurrency is a digital form of money based on cryptography technology. Cryptography is data encryption that does not have a physical appearance but exists only in digital form (distributed ledger). Its main features are anonymity, decentralization, and security.

Cryptocurrencies are circulated within the system directly (P2P/peer-to-peer) – without the participation of a third party. Each of the participants is equal. No one has privileges, regardless of their social or financial status. At the heart of this virtual money is a decentralized open database – blockchain. Blockchain is a distributed ledger allowing to send and receive transactions from one person to another.

Most cryptocurrencies have an emission limitation (the release of new coins into circulation). In the Bitcoin network, it is 21 million "coins." And in such cryptocurrency as Ethereum (ETH, ether), for example, there is no restriction on emission. Ethereum has a variable rate of emission and no supply cap.

Why Do We Need Cryptocurrency?

Cryptocurrency can be helpful for various purposes, from shopping to saving money. Here are a few major uses for crypto as a finance tool:

• Payments. And not just transactions but anonymous, fast, and direct transactions. They are carried out between private individuals and for purchasing goods and services on the Internet.

• Money storage. It is almost impossible to "steal" crypto from a wallet. Since all operations are irreversible and use private keys, it is unrealistic to intercept or hack them. If you have not given your private key to anyone, your cryptocurrency will always be safe.

• Investments. Bitcoin and other cryptocurrencies are considered investment assets due to exchange rate fluctuations and an overall increase in popularity. Moreover, crypto is suitable for short-term earnings by trading on the exchange and long-term, as the exchange rate shows an upward trend.

• Business. More and more companies and services are starting to accept payments in cryptocurrency transactions. Crypto startups that raise funds through ICOs (crowdfunding) have become everyday things. You can initiate fundraising through an ICO if you have a business idea related to blockchain or virtual currency.

Luckily, cryptocurrency is not the only use case of the blockchain. Looking at this technology separately from digital currency, the list of current and potential future use cases goes on and on.

Crypto VS Fiat

When the word "currency" is mentioned, images of banknotes and banks pop up in your mind. We are used to the fiat system in the financial sector, a standard, regulated currency such as a dollar or a euro. The main differences between cryptocurrencies and fiat currencies are:

• Cryptocurrency has no physical appearance. Yes, fiat also exists in electronic form, but there are no banknotes and no cryptocurrency coins. Make sure to distinguish physical coins, storage wallets, and QR codes that work with crypto with actual physical currency.

• Cryptocurrency is not issued by the central bank and is not tied to the economy of any country. No one controls the primary issue and the following emission of cryptocurrency. No one can influence these processes. The price is formed by supply and demand on the market. It is not directly connected with the economy of any country.

• Cryptocurrency is anonymous. To work with a bank or payment system (Paypal, Venmo, etc.), you must specify at least part of your personal data. Cryptocurrency doesn't require anything, just like paper cash. Each member is anonymous. All information about the owner's wallet (account) is a set of characters in the wallet address (example of wallet address: 19emjx4vqHPn6ZTsh1ZNbBD7uFZqWA5Cq)

Bitcoin Wallet Address Example

• Direct transactions. This virtual currency system has no processing centers, intermediaries, issuers, and third parties. The transaction goes from Alice to Bob directly, like giving cash to someone physically. No one can suspend, recall, freeze, or cancel the transaction. All transactions are irreversible, so if you receive bitcoins in your wallet, you can be sure that no one can take them away.

How Does Cryptocurrency Work?

Most cryptocurrencies function and circulate on the blockchain. This is an open, decentralized database where information about all transactions is recorded and stored. It is not located on any separate computer, server, or hard drive, but is divided into nodes. It is supported by active members of the network – ordinary users of full-fledged wallets.

Individual cells with recorded data are blocks. Moreover, all the blocks are interconnected in the chain – from this comes the name Blockchain.

Blockchain Simplified Block Creation Process

The connection is established by writing the hash of all previous blocks to the new block. Because of this, it is almost impossible to change a separate block – you will have to "hack" all the blocks in the chain.

Hash is simply a result of all data included in the transaction/block encrypted into a single alphanumeric string. To illustrate, let's take a phone number +1-617-949-4546 and sum all numbers multiple times:

• 1+6+1+7+9+4+9+4+5+4+6 = 56

• 5+6 = 11

• 1+1 = 2 – this number is called hash sum or simply hash.

The prefix "crypto" is because Bitcoin and other currencies use encryption and cryptographic hash functions. So each member of the network has a private key and a public key. The private key is used to sign a "transfer of ownership." This is the basis of all transactions and ensures the transfer of cryptocurrency from one participant to another. And the public key is used to verify other people's transactions in the blockchain. In other words, a private key is a secret signature that lets the blockchain know that the transaction is legitimate, and a public key is the account number that you can share with anyone to receive money.

How to Store and Use Cryptocurrency?

To use Bitcoin or any other coin or token, you need a cryptocurrency wallet and buy/receive Bitcoin. The majority of beginners store their coins on the cryptocurrency exchanges where they purchased them. This is a risky storage method because centralized exchanges don't create a unique wallet for you. They make a record in their system saying that user johnstone@gmail.com bought 1 BTC, and they promise to deliver your Bitcoin upon request. If you decide to keep your "promised" bitcoin on such an exchange, you will lose it once the company files for bankruptcy or is hacked. This has happened multiple times since 2009 (e.g., MT.Gox exchange hack) because crypto exchanges are lucrative targets for hackers.

The safest way to store cryptocurrency is offline on a hardware wallet (also called a cold wallet) to protect yourself from hacking and theft of funds.

• Ledger Nano S

• Trezor One

The hardware wallets, Ledger Nano S and Trezor One are considered one of the safest. Both support more than 1000 cryptocurrencies and cost around $60. More expensive products from both companies are also available, so feel safe to shop for other models. The wallet is easy to set up, and you can immediately transfer the cryptocurrency purchased on the exchange. Make sure to buy wallets from the official store or reseller, and check the box upon arrival. I don't recommend buying it from Amazon or eBay due to the risk of receiving a wallet where your private key has been exposed. If your package is damaged or opened – never use such a wallet. It most likely was compromised on the way from the manufacturer to your home. Suppose the seller is official, and the box looks unopened. In that case, you can start using it as your safe cryptocurrency storage device.

Cryptocurrency Mining: where does crypto come from?

The most common method of cryptocurrency issue and emission is through mining. In Bitcoin, mining is solving cryptographic tasks of varying complexity using computing equipment capacities. There is also forging – a particular form of crypto mining with voting and initial cryptocurrency emission (ICO - Initial Coin Offerings).

Bitcoin Mining Illustration

Why is this necessary at all, and why do miners get rewards? This process is similar to how torrent trackers work. The participants of the tracker are engaged in the distribution of files. For this, they receive a rating, which is subsequently used to download new data. As peers in torrent trackers distribute files, miners are using computing power to maintain network performance.

The ultimate goal of mining is to reach a secure, tamper-resistant consensus by compilation of a digital signature (hash) that closes the block. As soon as the block completes, the miner receives a reward, and a new block begins to form. Different cryptocurrencies use different computing power, such as processors (CPU), video cards (GPU), or specialized equipment (ASIC, FPGA). Mining is one method of earning cryptocurrencies.

The following protocols (consensus algorithms) are used to determine the mining method:

• Proof-of-Work (PoW). This is a security algorithm in which the authenticity of transactions is verified through the performance of specific tasks. In PoW, the higher the equipment performance, the more coins are mined.

• Proof-of-Stake (PoS). This concept states that you can mine cryptocurrency or validate block transactions and receive a reward according to the number of coins you have stacked. PoS is a "credit" mining. The more coins are stacked, the greater the reward.

• Proof-of-Activity (PoA). PoA is a hybrid option between PoS and PoW that attempts to bring the best of both.

• Other less common protocols include Proof-of-Capacity, Proof-of-Burn, and Proof-of-Storage. By the time I finish writing this series, a few more will most likely be introduced.

The choice of equipment and its power depends on the hashing algorithm. Bitcoin has SHA-256. This algorithm is "tied" to equipment performance. Litecoin has Scrypt, a modified SHA-256, with great emphasis on RAM.

SHA-256 is a one-way function that converts a text of any length into a string of 256 bits. This is known as a hashing function. In this case, it is a cryptographically secure hashing function. The output of such a function tells you very little about the input.

Examples of mining equipment

How to Get or Buy Cryptocurrency

In addition to mining, there are many other, more straightforward ways to earn cryptocurrencies. Let's consider some of them:

• Faucets. Faucets are services for distributing Bitcoin and other coins for performing small tasks: solving the captcha, web surfing, and so on.

• Bounty. Bounty is the process of advertising new crypto projects through social media posting, reposting, document translations, and so on. Initially, you get tokens for free, which will soon become a full-fledged cryptocurrency.

• Blogging/copywriting. Members of Steemit – a social network owned and operated by its users – receive a reward in the form of internal cryptocurrency when making a new post. Later, you can sell it on exchanges.

Bitcoin and alternative coins, or simply altcoins (Ethereum, Ripple, etc.), can also be easily purchased. This is done through cryptocurrency exchanges, BTMs (Bitcoin ATMs), or directly from other people. If you want to buy crypto online, it is enough to have a debit or credit card. However, most legit exchanges require proof of identity, so don't be surprised if you are asked to provide a picture of your ID. This is because of the regulations governments put in place to reduce the anonymity of crypto users. You can also buy crypto with your fiat money (cash) using machines installed in shopping malls, convenience stores, and gas stations. Usually, the price is 5-10% higher than you see on big exchanges, so this is a less popular option.

Are Cryptocurrencies Legal?

Cryptocurrencies are legal in most countries, although there may be restrictions on their use or exchange. For example, in 2021, the United States government proposed regulations on cryptocurrency transactions that could go into effect by 2022. Additionally, some countries have imposed taxes on cryptocurrency transactions or exchanges. Despite these regulations, cryptocurrencies remain a viable option for users who want to make secure and anonymous transactions without involving traditional banks or other financial institutions.

What are the Types of Cryptocurrency?

In general, cryptocurrencies are divided into two forms, coins and tokens. What is the difference between a "Coin" and a "Token"? A Coin is a cryptocurrency that can operate independently. A Token is an asset that depends on another cryptocurrency as a "hosting" platform. The most popular "token platform" is Ethereum, on which most tokens are based. Ethereum is the second largest cryptocurrency after Bitcoin and has the most currently known use cases (DeFi, NFTs, games, etc.), while Bitcoin is designed for financial transactions (DeFi) only.

Why Does Cryptocurrency Have Value?

How reasonable is cryptocurrency's price, and how is it supported? There are different opinions on this. In the summer of 2017, the American IT billionaire Mark Cuban criticized Bitcoin and the crypto as a whole on Twitter:

Anyone anywhere can buy a stock. #crypto is like gold. More religion than asset. Except of course gold makes nice jewelry. #crypto notsomuch https://t.co/xp334BCRa2

— Mark Cuban (@mcuban) June 6, 2017

After that, the rate declined, and Mark added:

You know it’s a bubble when a random twitter thread bounces the price. https://t.co/7gBGYU3JcQ

— Mark Cuban (@mcuban) June 6, 2017

However, later, Cuban began to invest in ICOs and even advised people to keep 1/10 of their funds in cryptocurrency. There are two main features for a "successful" currency to exist – a store of value and a medium of exchange. Besides, there are essential features such as scarcity, divisibility, utility, transportability, durability, and the ability to counterfeit it. In short, bitcoin meets all of the qualifications even better than fiat money. However, there is still an issue with cryptocurrency's status as a store of value. Like regular fiat currencies, most cryptocurrencies, including Bitcoin, are not backed by the economy, precious metals (gold, silver, etc.), or other commodities. The value of Bitcoin has been driven mostly by the speculative interest of market participants. Due to the relatively low evaluation (market capitalization) of cryptocurrencies compared to, for example, the stock market, it is easier to manipulate the price. Thus, artificially inflating or deflating the bubble. This is likely to decline as Bitcoin continues to see greater mainstream adoption and a constant increase in market capitalization, which makes it harder for a single manipulator to influence the price.

So what drives the cryptocurrency price?

Firstly, cryptocurrency mining requires powerful equipment that consumes a lot of electricity and gradually loses its performance. It turns out that depreciation is partially transferred to the value of the coins. Miners are the ones who bring newly mined coins onto the market. Since mining is quite an expensive process for every miner, they wouldn't want to sell their coins cheaper than they spent on mining. This creates a scarcity that also significantly influences the price. The reduced supply of coins with the same or rising level of demand pushes the price up.

Secondly, blockchain technology. Blockchain is something that no other payment system has. The blockchain is universal, reliable, and decentralized. At the same time, it guarantees anonymity and high transaction speeds. And it is used in various fields, from the financial sector to alternative energy. These are some obvious advantages that help determine the value of cryptocurrencies.

The market determines the value of these virtual coins. The greater the demand for a particular cryptocurrency, the higher its value. Demand, in turn, depends on the advantages that the coin offers. If tomorrow BTC is accepted as the official currency of China, for example, then its value will soar. Demand is heavily formed based on news, new developments, company announcements, and other factors.

There are also speculative leaps in the price – the so-called "pumps and dumps". They are provoked by large traders (manipulators) on exchanges seeking to make money out of thin air. They are not particularly interested in how much the coin costs. Having many assets, manipulators can have a short-term effect on the exchange.

Advantages and disadvantages of cryptocurrency

Let's summarize the crypto advantages we discussed so far and introduce some disadvantages to complete the picture.

The high price volatility is one of the main drawbacks of cryptocurrencies and the primary reason for mistrust. What about the other disadvantages of digital currency, though? For example, regulation. Initially, BTC was a fully decentralized and independent currency. This means that the network member in the USA and the network member in Burkina Faso are equal. However, more and more countries are thinking about regulating cryptocurrencies. And in some parts of the world (Bolivia, Indonesia, Thailand) it is prohibited at the government level. The disadvantages also include reputation. Due to its anonymity, cryptocurrency has become a payment tool used in the black markets. A potential drawback is the "51% attack" threat when 51% of mining capacity or 51% of all coins (in the case of Ethereum) fall into the hands of one participant. Then this participant will completely control the blockchain and will be able to duplicate transactions. This is practically impossible because doing so doesn't make any financial sense cost-wise. See the illustration below to understand a "51% attack better".

Bitcoin's “51% attack” explained

In other words, no one will benefit from such an attack. Moreover, the more extensive the network, or the more users holding cryptocurrency, the more difficult it is to make the "51% attack".

Summary

Is there a future for cryptocurrencies? It is difficult to answer the question because everyone has their own definition of the word "future". Is the timeframe 10 years or 500 years from now?

However, the present is closely related to digital currencies. Since its introduction in 2009, the possibilities and popularity of cryptocurrencies are only growing. Therefore, we should expect intense crypto development in the first half of the 21st century.

Keep Exploring

Start exploring the world of cryptocurrencies by visiting the CoinMarketCap (CMC) website. It has a list of more than 2,500 cryptocurrencies with descriptions of their purpose and market metrics.

A quick overview of the columns on CMC and its meaning:

• #: the list is sorted by market capitalization (Market Cap).

• Name: the name of the cryptocurrency.

• Price: the value of one unit (coin or token) at a given time.

• Market Cap: Market capitalization refers to a cryptocurrency's total dollar market value. It is calculated by the following formula: Price x Circulating Supply. If there are 100 coins on the market with a price of $5, then the market cap is $500 (100 x $5).

• Price: the current exchange price of the cryptocurrency.

• Circulating supply: the number of coins on the market.

• Volume (24h): number of coins traded on exchanges during a given day in a USD value.

• Change (24h): change in price for the last 24 hours displayed in a percentage.

• Price Graph (7d): visualized change in price for the last 7 days in the form of a chart.

What is MVC: Theory

A static HTML page doesn't know how to react to user actions. Two-way interaction requires dynamic web pages. MVC is the key to understanding dynamic web application development, so a developer needs to know this concept.

MVC is a concept or programming paradigm that stands for Model-View-Controller. It is a way of organizing source code that separates the blocks responsible for different tasks. One block is responsible for the application data, another block is responsible for the appearance, and the third block controls the application.

MVC Components:

• Model - This component is responsible for the data and defines the application's structure. For example, if you create a To-Do application, the model component code will define the task list and individual tasks.

• View - This component is responsible for interacting with the user. That is, the view component code defines the user interface of the application and how it is used.

• Controller - This component is responsible for the communication between the model and the view. The controller code decides how the website reacts to the user. In other words, it is the brain of the MVC application.

Advantages of MVC Pattern

The MVC pattern brings a lot of advantages to the table, some of which are discussed below.

• Scalability: The MVC pattern makes adding more resources to an application easier. This is because the model, view, and controller are entirely independent of each other and don't have to be modified when new resources are added to the application. This enables developers to add new resources to the application, such as new servers, new databases, etc., without having to refactor the application's code.

• Maintainability: Another advantage of using the MVC pattern is better maintainability. The three components of the MVC pattern are self-contained, making it easy to troubleshoot issues and make changes.

• Better Code Quality: Since the MVC pattern is widely used, many resources are available on the internet to help developers implement it. Moreover, plenty of tools make it easier for developers to create applications using the MVC pattern.

How MVC is like a sandwich shop

Imagine coming to a store or cafe where you can order a sandwich. There are tuna, turkey, and ham sandwiches on the menu. You order a turkey sandwich. The seller understands you from half a word, turns toward the kitchen, and tells the cooks to make a turkey sandwich.

The cooks have various products on hand: tuna, turkey, ham, cheese, lettuce, and other ingredients to add to the sandwiches. They pick just what they need for your turkey sandwich. You get your order.

We can describe the purchase of the sandwich through the MVC:

• Model: the kitchen where the cook makes the sandwich

• View: the finished sandwich that you are happy to eat

• Controller: the vendor or bartender who takes the order and passes it on to the kitchen

You already visualized a prepared turkey sandwich when you ordered it from the bartender. This is called View.

In the same way, you can imagine interacting with a website. When you go to Google and search for "sandwich shop near me", you expect to see a list of websites and map locations as a search result.

When you hit "Enter", the browser sends the request to Google's servers. It includes the request to READ the list of available resources matching "sandwich shop" near your IP address or mobile device's current location. This request is similar to making a turkey sandwich order and is called the Controller.

Once received, the request is processed on Google's server. The program pulls all the relevant businesses selling sandwiches from the database to show the list. This can be compared to the kitchen and cooks in the sandwich example and is called a Model.

The Google server takes the matching shops from the database and prepares your order: a list of texts, links, and images. That's what the cooks in the sandwich store kitchen were doing. It's a View again.

MVC concept in Web Development

How the Controller works

The controller handles incoming requests. In the framework, this can consist of defining the specific URLs (routers) the user reaches when they click a link or a button. Consider this with the example of a site that gives the user a list of his friends:

Click to website.com/profile/ -> 
returns profilewebsite.com/friends/ -> 
returns friendswebsite.com/friend={userName}/ -> 
returns the profile of a particular friend

How the Model works

The Model is responsible for the data stored and processed on the server. It will listen to the Controller and retrieve or update the database based on the request (GET/POST/PUT/DELETE). User: { userName: { firstName, lastName }, friends } Here is an example of a Mongoose user Schema in MongoDB, ensuring data consistency.

// 1. Referencing Mongoose
const mongoose = require('mongoose')

// 2. Defining the Schema
const UserSchema = new mongoose.Schema({
  userName: { type: String, unique: true },
  email: { type: String, unique: true },
  password: String
})

// 3. Exporting a Model
module.exports = mongoose.model('User', UserSchema)

Mongoose is an Object Data Modeling (ODM) library for MongoDB and Node.js. It manages relationships between data, provides schema validation, and is used to translate between objects in code and the presentation of those objects in MongoDB.

While MongoDB is schema-less and accepts any type of data, it is a good practice to create a Schema to reject inconsistent data inputs.

How the View works

The View is the combination of an HTML template (e.g., EJS, Pug, ReactJS) and CSS that the server returns after processing the request. You get a web page listing friends if the request is processed correctly. If the request is invalid, you get a 404 error page. ```

• Friend 1: {friendList[0].userName}

• Friend 2: {friendList[1].userName}

• Friend 3: {friendList[2].userName}

• ...

Implementing the MVC Pattern

This section will discuss how to use MVC pattern in a web application. Let's assume we want to build an e-commerce application for an online computer store. And let's further assume that we want to display the details of a computer on the homepage. We will use the following domain terms to discuss the implementation of the MVC pattern in our application.

MVC Architecture in Different Programming Languages

The MVC pattern can be implemented in various programming languages. Let's discuss how the MVC pattern is implemented in some popular programming languages.

• JavaScript: The Node.js framework follows the MVC pattern.

• Python: The Django framework follows the MVC pattern.

• Ruby: The Ruby on Rails framework is designed to implement the MVC pattern. However, the application's structure may vary slightly from other Ruby MVC frameworks such as Sinatra and Grape.

• Java: The Spring Framework follows the MVC pattern.

• PHP: The Laravel framework follows the MVC pattern.

• C#: The ASP.NET MVC framework follows the MVC pattern.

Scaling Applications with the MVC Pattern

The MVC pattern is the most widely used architectural pattern for developing robust and scalable applications. However, it must be appropriately designed to scale an application with the MVC design pattern. Let's understand how we can do that.

• Model: The model may contain database tables containing the application's data. If the database tables have many records, we need to store the data in a database that can handle large amounts of data. If the database tables have a low number of records, we can store the data in a database that can handle a low number of records.

• View: The view may contain the front-end code of the application (user interface). The front-end code is responsible for the interactions of the user and the data displayed on the screen. The front-end code should be decoupled from the database so other applications or software can reuse it.

• Controller: The model may contain the database containing the data displayed on the screen. If the database is small, the controller can directly fetch the data from the database and pass it to the view. However, if the database is large, the controller should fetch data from the model that can handle large amounts of data and store the data in a database that can handle a low number of records.

Best Practices for Using the MVC Pattern

While the MVC pattern is widely used, it is important to use it correctly. Here are a few best practices to help you implement the MVC pattern more effectively.

1. Make sure all your business logic is stored in the model. Do not put any business logic in the controller or the view. This will make the application more scalable and easier to maintain.

2. Use independent components in the application. This will help the application scale better.

3. Use a database that can handle a large volume of data. This will help in scaling the application.

Conclusion

MVC is an approach to application design that involves separating code into blocks of model, view, and controller types. The Controller processes incoming requests. The Model retrieves the information needed to execute specific queries from the database. The View defines the result of the request that the user receives.

MVC not only allows abstracting the server and the database from the user but also helps structure the app so that it is easier to navigate during development and simplify the team collaboration process on various parts of the web application. For example, if you want to change the templating language from EJS to Pug, you go into the Views folder and have everything isolated. To change the database from MongoDB to SQL, you go to Models without stressing about breaking Controllers or Views.

Inspired by the following sources:

• What is programming MVC? (DevMarketer)

• What is MVC, and how is it like a sandwich shop? (Adam Wattis)

Read on to find out why I decided to conduct such in-depth research and how it can take you or your business to the next level

or jump to the list of websites now (available in Google Sheets and Airtable).

As a web developer with a marketing background, I know the difficulties other devs and up-and-coming tech companies face. Putting your business on the map at a low cost is no small feat.

Since one of the growth hacking ways is organic growth on search engines, I initiated extensive research to help me and other devs bootstrapping their way to success by taking their first link-building steps and getting exposure on high-traffic websites.

Here are a few reasons to consider submitting your project. By doing so, you could:

• Get press coverage
• Boost your website's organic traffic
• Promote your product or services for free
• Find early adopters or cofounders
• Get early feedback on your prototype or software beta features
• Pitch your business before launch and gain early user traction
• Score extra funding in the development phase
• Find networking and partnership opportunities
• Build online visibility and brand awareness

If at least one of those made you nod in agreement, you're in the right place.

How I Came Up with the Startup Directories List

I am a member of a few SaaS communities, and one question that repeatedly appears in many groups for new startups is, "Can you share a list of websites where I can launch and promote my startup?" .

Is clicking hundreds of URLs and deciding if you should publish your startup there your thing? Didn't think so. That's why I chose to help founders save hundreds of hours by rethinking the way lists of startup directories are created.

How Did I Conduct the Research?

First, I crawled and audited all the available data from similar lists. Startup directories, such as those found on GitHub and Submit.co websites are the few standing out in terms of quality.

But they still need more critical information, like traffic potential or domain authority, to name a couple. So I decided to take things further and reviewed each startup directory list published since 2010.

Most resources on startup directories available online come from 2019 at best and lack valuable data or filters to narrow down the list. About 30% of links on existing lists of startup directories lead to closed, abandoned, or pivoted websites.

It sounds like a massive waste of time founders can't afford. So I decided to propose a solution for new startups out there. I manually went through every platform to ensure you never landed on a dead or irrelevant website.

Analyzing 99 crappy websites was worth it if there was a chance to get your startup at least one excellent backlink.

Here are the criteria I followed when manually crawling websites to submit your startup:

1. Is the website active? Does it publish new content regularly?
2. Is it relevant for digital startups and side projects (including games)?
3. Is there a direct way to create a listing or share content for publishing?
4. Would I publish my project there?
5. Is there any value for link building or brand awareness implied?

After gathering raw data and deduplicating it, I ended up with 2,016 websites. The next step was to exclude the ones with low DA and SEO potential.

To enrich my brand-new list of startup directories, I took the following data points into account:

• How long does it take to submit your startup?
• Is the directory free or paid?
• How difficult is submitting your startup here?
• Moz Domain Authority (DA)
• Traffic volume
• The top country in terms of website traffic
• Website type (media, directory, forum, etc.)
• Website's core topic
• Trust and Citation Flow scores

The icing on the cake is the startup directory filtering. With this list, you can filter all the data according to your business needs and focus on directories that fit your product criteria.

Things to Consider Before Submitting Your Startup

After conducting market research, creating a team, and building an MVP comes the most challenging part of the startup lifecycle: promoting your SaaS product online, successfully showcasing your services to your audience, and getting the first users.

This list of websites to submit your startup is made to help you bring new products in front of early adopters or investors and improve your website authority by increasing exposure.

Before you promote your company in the media, let's cover the basics so you can decide which submission websites are a good fit and which are worth skipping.

What is Website Authority and Why is it Essential?

Google algorithm is an extensive, complex beast. There are likely thousands of ranking factors, and the list keeps growing.

It would help if you gained Google's trust (aka authority) to get more search traffic in the long run. And one of the most effective digital marketing techniques is link building.

If you are bootstrapping your product, a question like this will arise: "Can I just pitch my business everywhere or buy backlinks for pennies from high-volume resellers?" . Huh, if everything were that simple, SEO agencies wouldn't exist.

To get your domain authority (DA) growing, you need to get featured by websites with a higher domain authority than yours. DA is a metric defined on a scale from 0 to 100.

1. Compare your company website DA with a target website DA using free website authority checkers by Ahrefs or Moz. If the target website DA is higher than yours, that's a go-ahead signal to submit your startup there.
2. Another vital factor to consider is topical similarity. It means you want to get backlinks from websites that are relevant to your niche. If you sell a SaaS product for developers, backlinks from cooking blogs will get you nowhere, despite a higher DA and decent traffic volume. While there's more to it, this should suffice to choose from business media and startup ranking directories featured in our list.

Top Websites to Submit Your Startup

Here is a sneak peek of the startup directories that made it to our list. The following platforms should give you an idea of the quality I kept in mind while creating the directory list. Links to the complete list are available at the end of the section.

#IndieHackers Indie Hackers is a collaborative community that brings tech business founders together. SaaS companies and B2B entrepreneurs share success stories and growth insights here. A startup owner like you can learn much about marketing new products and reach the target audience by getting your project featured on Indie Hackers.

Product Hunt

Chances are you don't need an introduction to the #1 go-to website to publish a startup or a side project. In case you do, Product Hunt is a digital platform where you can find the top new products and businesses. Share and geek out about the latest software, mobile apps, websites, hardware projects, and other creations with like-minded people.

If you plan to submit your startup on Product Hunt, get ready to spend some time preparing for a launch. This How to Launch on Product Hunt guide by the PH team should help you with that.

Startup Stash Startup Stash is a startup directory of tools and resources for entrepreneurs. This platform has everything you need for your startup liftoff: from investors and product development software to launch insights and showcasing opportunities. Startup Stash is also the most upvoted service on Product Hunt.

Starter Story StarterStory is a startup directory platform interviewing successful entrepreneurs and providing insights about launching products and running a business. Each post covers how entrepreneurs kick off their projects, build visibility, acquire users or investments, and deal with daily challenges. Have a startup story to share? StarterStory is an excellent place to do so and get feedback from the community.

F6S F6S is a global community of 16,000 enterprises and startup projects. Their service connects new startups and companies with early adopters, accelerators, angel and venture capital investors. On the F6S platform, you can also find jobs, grants, partnerships, and exposure opportunities. They offer help to get your startup and side projects up and running.

Here are a few more great directories for new startups from the list:

• YourStack
• AngelList
• Listly
• 10words
• InnMind
• Makerlog

🚀 The complete list is available in Airtable and Google Sheets below. Choose the one you prefer and make it yours!

You can get a copy of the list and reuse it however you want. Just make sure to cite me if you are going to republish it.

How to Save Time Publishing New Startups

After you are done using the filters and identifying the best directories to feature your startup, you should end up with about 20 websites.

The next challenge is preparing a perfect pitch and other info you will attach to your listings and company profiles. Here's what you need to prepare in advance to save time on retyping the same things over and over again:

1. Website URL
2. Your Logo
3. Your Location
4. Number of Employees
5. Target market segment
6. Information on your venture/angel fundraising achievements, if any
7. Approximately 3-5 screenshots/images of your products
8. Product video (Not necessary across all platforms)
9. Founding year
10. Founder(s) name
11. Founder(s) bio
12. Awards
13. Both brief & long descriptions (create about three copies of each for variation)
14. Tags
15. Who's the product for / What problems it solves
16. What makes your business different from competitors
17. Social media handles
18. Pricing details
19. 600-2,000 words article or press release about your product

As for the last point, chances are you're not thrilled with writing different copies for multiple websites. Instead, you can use tools such as Writesonic to assist with copywriting or hire content writers on Upwork.

Some websites request even more business information, but these are the most common points. Have it ready before you go through the list.

Despite the substantial amount of time saved on gathering, cleaning, and enriching the list, you still need to invest 5-10 hours reviewing the list and submitting your startup information. Here is a better if you have an extra $100 budget to save a hassle.

Here is a step-by-step guide:

1. Create a Google Drive folder with all information about your company.
2. Create a copy of the prepared list and save it with all the filters applied.
3. Hire a virtual assistant on Upwork or Fiverr for $5-10 per hour.
4. Share access to the folder from Step 1.
5. Monitor the performance.

Tip: Add an extra column into the spreadsheet with your list where the freelance assistant will place submission URLs for you to track.

How to Track Results after Getting Featured

Below is the list of software and KPIs to keep an eye on after submitting your business:

Freemium tools with limited features: Ahrefs or Semrush

• KPIs: Domain Rating (Ahrefs) or Authority Score (Semrush), Referring domains, Backlinks, Keyword Rankings

Free service: Google Analytics

• KPIs: Traffic volume and Conversions from Organic and Referral sessions.

Conclusion

Now all you need to get your startup's initial organic traffic and awareness momentum growing is to find the right words for your perfect pitch and write down all the essential info about your business.

Let's do a quick recap of how to publish your project using this directories list:

1. Get your copy of the startup directory list.
2. Filter it according to your website's DA, topic, and other values.
3. Prepare your startup pitch and other essential info about the company.
4. Organize files from Steps 1, 2, and 3 in a Google Drive folder.
5. Hire a freelancer to post info from Step 3 on websites from Step 2.
6. Track results for 2-3 months. Your traffic, DA, and rankings should improve.

The last step is to leave a comment below when your product is live. 😉 I wish you all the luck in the world!

"Education is not the learning of many facts, but the training of the mind to think." Albert Einstein

Back in the day, when I decided to step into the programming world, I took some time planning to avoid the bumps that came my way in the past. I knew that software development would be the hardest, most memory-consuming, and brain-twisting subject I had ever learned. Therefore, my first question was:

• Are there better ways to learn? If yes, what are the best methods for improving learning efficiency?

Aside from complexity, it was obvious that I would be learning from dozens of sources (digital and physical) and different settings (home, commute, office). This would create a mess of notes, links, and media across books and multiple devices, leading to the second question:

• What tools do I need to excel in studying without drowning in materials to maximize the takeaways I learn?

In an attempt to answer these questions, I came across a few mindblowing studies and materials that left me wondering, why on earth this isn't taught in schools yet?! The "system" or methodology I acquired after my research satisfied me. I still use it and find it highly efficient. After reading, you will be able to improve your learning skills, and the outcomes will help you improve at whatever you are trying to excel in.

Why standard learning methodology is broken

Rereading

One of the most common revision techniques that students use in their studies is rereading when they repeatedly get back to the source of information to remember more details from it.

There have been lots of studies analyzing its efficiency. Some of them are listed in the list of references.

J. Dunlosky, one of the authors of "Improving Students' Learning With Effective Learning Techniques..." research summarized:

Based on the available evidence, we rate rereading as having low utility... although rereading is relatively economical with respect to time demands... when compared with some other learning techniques rereading is also typically much less effective.

Given that a few pieces of research have shown that rereading has low utility, I concluded not to waste time doing that.

Highlighting and underlining

Highlighting is another very popular studying strategy. Luckily, several solid pieces of research were done on highlighting I could get advice from as well. Summarizing the same research "Improving Students' Learning With Effective Learning Techniques...":

On the basis of available evidence, we rate highlighting and underlining as having low utility...

It may actually hurt performance on higher-level tasks that require inference-making.

It feels productive to colorize the book and gives a sense of a safety blanket. You know that whenever you need this information in the future, you will easily find it in the book. The problem is that you create a reference to that highlighting point but need to put the piece of knowledge in your long-term memory instead. On another note, will I remember the highlight location, given so many materials to come in the future? The research says we could be doing more efficient things.

Summarizing method (note-taking)

This is my favorite part of the conclusions I've made. My laziness screams when I have to summarize. All teachers in my life advised this technique to solidify the material. What a relief it was to learn there is a better way to learn than summarizing.

Even though a few studies are concluding that students who summarize the topics well, perform slightly better than others, it's hard to test this. As you can imagine, different people have various quality of their summaries. Hence you never know if it helps or not.

Another conclusion by J. Donlosky from the same research says:

On the basis of the available evidence, we rate summarization as low utility.

It can be an effective learning strategy for learners who are already skilled at summarizing; however, many learners (including children, high school students, and even some undergraduates) will require extensive training, which makes this strategy less feasible.

The "why"

Before going straight into the methods, let's recap what is at stake if we keep learning ineffectively. We could have been doing the same as always, reading, highlighting, taking notes; it brought us to where we are, we survived, and why bother, right?

Well, try learning something dense in terms like medicine, programming, or formulas-rich like mechanical engineering or architecture. The chances are you'll end up with something like:

• Low competitiveness. Always in need of an external resource to rely on (books, notes, google).
• Wasted time and money on content consumption. Consumed a ton of materials and felt like you got it but ended up with a blank mind in front of a practical task.
• Limited career choices and a mediocre path. If your brain doesn't form enough neural links between bits of information, you can't be flexible and creative enough to offer something new to what exists.
• Zero to low return on investment in education. You are consuming professional content daily, paying for new courses, and piling notes to save all of that for a particular moment in the future when they will be helpful. In reality, you use only a fraction of it on some lucky day.

Any topic, especially programming, requires a lot of effort to remember concepts and facts that become a platform for future practice and innovation. However, practical tasks appear surprisingly uncommon when they are not placed well enough in the memory and adequately massaged.

Sub-conclusion

• Common learning methods provide the direction and a sense of a safety blanket but fail when you need to take knowledge into practice.
• Rereading and highlighting should be thrown away due to low utility and least effective learning methods.
• Information seems handy, but when I need it, the memory returns "404 - Page Not Found".
• Summarizing can help if you are trained and have developed a high-quality output, but there are more effective options.

Since we learned what not to do, let's find methods that beat the above by eternity and don't require groundbreaking efforts.

The Most Effective Learning Formula (by far)

Effective Learning = Active Recall + Spaced Repetition

1. Active Recall

Active Recall means that to start solidifying the information in our memory, we need to take it out without external help.

This is the opposite of standard methods like note-taking or rereading when you passively get back to something. Active Recall forces you to go through the jungles of the memory (neural links) and build the speedway, so the moment you need to remember something, you have a straight, green light path to the memory slot with the required information.

To prove the point, below is the result of a study made in 2010 by Andrew C. Butler (Journal of Experimental Psychology) comparing how different students handled the test. Half of the students took a practice test after the study session (blue bar), and another half used typical studying methods, such as rereading, highlighting, etc. (white bar).

Students who did the practice test (active Recall) had 30-60% better results than those who didn't. This was the first "Aha!" moment. Now I know something that will give me an edge, comparing not only to my previous way of learning but also to others who are still learning ineffectively.

On one side, I have to make the mental effort to recall material after each study, which isn't the most pleasant thing to do, as the brain is lazy (a.k.a. energy efficient). But on the other side, I don't have to waste time rereading material, writing it down, organizing, and remembering notes' location. What a time saver!

Active Recall Strategies

I found a few strategies that work well within the Active Recall strategy.

My favorite one is the Cornell note-taking system. Instead of taking a note by writing down what just was heard or read, the better strategy is to write down questions about the paragraph or a chapter while reading. After finishing reading, watching, or listening, you should close the source and do your best to answer the list of collected questions. If not possible, get back and revise, close the source and try recalling it again.

By this, instead of mirroring what was just consumed, you should have your version of the studied material in your voice and your words. This also helps to iron the road and build new neural links around the fact or concept.

TOOL TO USE

I like using Notion as a collection of questions and answers on any material I come across and want to make sure to memorize. No matter where I am, I can snap a question on my phone or laptop and be sure it is accessible whenever I need it.

2. Spaced Repetition

The Forgetting Curve

Active Recall is by far the best method to grasp the learning material and place it in your brain. However, it still doesn't solve the problem of forgetting stuff in a week, month or year (!sic).

No matter how well you understand and recall, you will forget things exponentially.

The main idea of the forgetting curve and how we can take advantage of it is that every time we interrupt it, we reset it for a more extended period. In other words, the more often you recall things, the longer they will not be forgotten.

This is called flattening the forgetting curve. Source: Practical Psychology

The problem with our memory is that we retain only about 80% of the information after 24 hours from studying something. In three days, we retain only 60%; in 6 days, more than 80% is gone. How crazy and, unfortunately, relatable this is, I thought! This is like working hard to earn $1,000 and having more than $800 evaporated in one week without spending a dime.

That is where spaced repetition comes in. I like to think about it as insurance. You have to pay for it by making mental efforts, but you are confident that whatever you placed into the spaced repetition system, and more importantly in your brain, will stay there.

The study above suggests repeating new material in at least 1, 3, and 6 days gap between repetitions. This allows the brain to start forgetting the material between repetitions, and when the active recall day comes, you have to force some brain power to take this information out of the brain and flatten the forgetting curve.

To summarize Spaced Repetition, the more times we actively recall, the more spaced out our repetition becomes, and the more likely we are to encode this information in our long-term memory.

TOOL TO USE:

To incorporate and automate spaced repetition, I use the flashcard tool Anki App. I make sure to transfer all notes (questions and answers) from Notion into the Anki app and resurface them daily based on the spaced repetition.

Summary

Here are the answers to questions I made myself in the beginning:

Q1: Are there better ways to learn? If yes, what are the best methods for improving learning efficiency?

• To improve our learning efficiency and maximize our chances of solidifying new knowledge long-term, we need to transition from traditional strategies, such as rereading, copy-paste note-taking, highlighting, and summarizing. The science suggests two strategies for this transition to happen: Active Recall and Spaced Repetition, which we discussed above.

My outcomes

Here are a few things I highlighted after incorporating these strategies into my learning:

1. Started remembering way more information.
2. Use whatever I learn more often in practice.
3. Increased confidence in my learning abilities.
4. Identified the power of deep learning instead of remembering many facts.

I noticed that sometimes I only understood something once I placed it into the AnkiApp. In a few days of recalling the complex topic, I surf through it in theory and practice.

Q2: What tools do I need to excel in studying without drowning in materials to maximize the takeaways I learn?

• Notion + Anki App + some new habits

How I did it

By building these three simple habits:

1. Note the facts and concepts as questions and answers.
2. Add notes to AnkiApp or a similar app of your choice (Anki is the best IMO).
3. Incorporate studying Anki cards into the daily routine. I like doing it the first thing I start my computer in the morning, which takes 15-30 mins to complete.

So far, I have more than 600 flashcards (questions and answers) in my AnkiApp. The most fascinating and satisfying part is that I can randomly open anyone and give the correct answer on the spot.

Resources

Continue learning

1. How to study for exams - Evidence-based revision tips (highly recommend)
2. How to Study for Exams - Spaced Repetition | Evidence-based revision tips (highly recommend)
3. How To Use Anki Like A Pro (highly recommend)
4. Make It Stick - The Science of Successful Learning
5. Learning How to Learn (optional but super helpful)

Research References

1. Improving Students’ Learning With Effective Learning Techniques: Promising Directions From Cognitive and Educational Psychology (Dunlosky et al 2013)
2. Effectiveness of highlighting for retention of text material (Fowler & Barker 1974)
3. A powerful way to improve learning and memory (Karpicke, 2016)
4. Retrieval Practice Produces More Learning than Elaborative Studying with Concept Mapping | Science (Karpicke & Blunt 2011)