Altcoins are strictly speaking any coin or token other than Bitcoin. Let’s expand that definition to be more useful though: Altcoins are simply the lesser known coins and tokens.

Some of these are already traded on exchanges like Coinbase, so buying them is as simple as creating an account, connecting your bank, and clicking a button. One such example would be Celo Gold, which is already one of the largest tokens out there, but some may still consider it an altcoin.

But others are much harder to get your hands on. Currently, there are about 9000 of them listed on [Coinmarketcap](https://www.coinmarketcap.com) that are traded or swapped somewhere. 

Some of these have meteoric rises in prices in their early days, but only a few are listed on crypto exchanges, so many investors ask themselves: How do I get in on that?

What is an Altcoin?

Although they are called "wallets", crypto wallets are more like your bank account. And like that bank account, they allow you to accept transactions from anyone using the same blockchain, meaning you will need a different wallet for Bitcoin than Ethereum and so on.

Let’s understand what these wallets actually do: They are essentially nothing more than what is called a public address and a private key. Think of those as the same as your account number, and your online banking password: People can send money to your address or account number without your permission, but in order for funds to leave your account, you’ll need your private key or password.

Ever heard of those people who lost Bitcoins worth a fortune? You guessed it: They lost their wallet, and in it their private key.

So how do you choose a wallet you can’t lose? There are many options. 

You could simply print out your address and private key and put it into a safe location - that’s called a paper wallet, but isn’t very practical for most people and the information is easy to steal if you leave it out in the open. 

A variation of the paper wallet is a hardware wallet: A little USB device that saves those keys, but can be locked with a password or fingerprint. But you have to carry that with you wherever you want to use it. 

Another option is a little program, such as Metamask, that works directly in your browser. It’s a good middle-ground: Operated by you, but on your computer and ready to use when you need it.

And lastly, the most popular wallet is the online wallet, often provided by an exchange. They will create and operate your wallet on their servers. That’s very convenient, but the risk is that they can get hacked, or even just take your money and run. 

And now you know more about wallets: Just make sure you don’t lose them!


How crypto wallets work and which one to choose

You might have heard the term “fork” recently, especially since Ethereum is about to undergo such a “fork” to Ethereum 2.

But what does that actually mean? 

Just like reaching a literal fork in a road, from which your path could go into two totally separate directions, a crypto fork splits a blockchain into two versions going forward - the original one and the new fork. This is necessary, because blockchain technology evolves, and sometimes does so to the extent that it is not backwards compatible anymore.

In the case of Ethereum 2, it switches to proof of stake, which is a different form of transaction validation. Any computer that validated the original Ethereum transactions will no longer be able to apply the same logic to Ethereum 2. The owners will have to decide whether to stick with the old, or move to the new.

When that fork happens in 2022, Ethereum 1 and 2 will coexist. They are, however, different blockchains at that point and the aspiration is to make Ethereum 2 the new standard and slowly reduce reliance on the old one

But forks don’t have to be that disruptive. There are many blockchains, like Celo for example, which started with the Ethereum open source code, forked it, improved it, and launched their own blockchain, and in doing so, brought innovation to the ecosystem.

What is a fork?

Let’s take a look into those strange terms that crypto fans often use.

[Today's word? HODL.](https://www.google.com/search?q=hodl)

To "hodl" means nothing other than to hold a crypto currency, especially during a downturn when the market is selling off. 

The term originated on a Bitcoin forum in late 2013, when a user simply made a typo. They wrote "I am hodling" during one of the earlier Bitcoin bear markets, likely hoping to inspire others to do the same to stop the price from going down further.

The word “hodling” stuck around as a joke - first at the expense of the original author, later in general crypto culture. Eventually, it started to refer to the strategy of buying and holding, no matter what, in hopes for crypto’s takeover of traditional finance. 

Although it may have started as a joke at the expense of someone who simply mistyped something way back in 2013, who's got the last laugh now? At the time, Bitcoin was only $600. We hope they "hodled" indeed, because at its peak it was more than 100 times more valuable.


What does “HODL” mean?

Metamask is a browser extension and mobile app that acts as a wallet for crypto tokens that are based on Ethereum or compatible protocols. In plain English, that means you can accept, hold, and send almost everything with Metamask.

But what’s even cooler? Many websites, for example Uniswap, directly integrate with it, so as soon as you want to, say, swap a Token, a dialog pops up to connect Metamask. No need to deal with weird wallet addresses or separate logins and passwords.

You can set up your own Metamask wallet by going to [metamask.io](https://metamask.io) and following their instructions. Make sure you print out your recovery phrase and put it in a safe place - don’t be one of those people who lost their crypto passwords. 

If you want to add an altcoin, simply Google its name plus Metamask and you’ll likely find easy descriptions of how to integrate both.

Then you could send yourself tokens from your Coinbase account for example, so the wallet is funded. The crypto world is your oyster! 

What is Metamask?

To explain NFTs, let’s first remember how cryptocurrencies work: Every Bitcoin has the same value and utility: Meaning I can give you one of my Bitcoins, you give me one of yours in return, and we’d still have the same value. They are completely exchangeable by design. Another word for that is fungible.

Non-fungible tokens, or NFTs, are the opposite. They represent a group of assets that are not all the same. In fact, they are all different and one isn’t just like the other. Let’s take two digital images for example - both unique. They could be traded as an NFT. And just like with Bitcoin, the blockchain would record transfers to verify ownership.

So the difference between cryptocurrencies and NFTs is quite simple: While both can be traded on the blockchain, one represents an exchangeable value like a dollar bill, the other something that is uniquely valuable, like a collectible coin that is valued by its own rareness and unique condition.


What are NFTs?

Today we explain how “Proof of Work” works. 

First, remember that cryptocurrencies validate transactions by checking each transaction with multiple decentralized computers. And if enough of those all come to the same conclusion, they move on to the next transaction.

This is like asking a room filled with accountants to check your credit card statements. If they all have the same final balance, you trust the result.

But there is one problem - because things are decentralized, anyone can mine a blockchain, or become an accountant. Say I send a bunch of friends into your room and tell them all to cheat on the numbers, then you wouldn’t know which result to trust.

Proof of Work reduces the incentive to do that. Here, the accountants all have to solve the same math puzzle and the quickest of them gets to work on my credit card statements and collect a reward for doing so. But if someone cheated, the results wouldn’t add up, they would have wasted a lot of time on the puzzle, and everybody has to start over without getting a reward. What was a simple cheat before, now becomes so time consuming that I can’t convince my friends to help.
And that’s how proof of work also works in cryptocurrencies, only that the accountants are computers, the puzzle is an algorithm, and the statements are transactions.

And next time, we’ll talk about “Proof of Stake” in more detail, which is the alternative to “proof of work”.


What is Proof Of Work (PoW)?

The biggest problem with making cryptocurrencies like Bitcoin usable as payment methods is that their price fluctuates heavily. 

Imagine you feel like eating a steak, and there is just enough Bitcoin in your wallet to buy one, but you fall asleep on the couch. The day after, you walk into the restaurant and all you can get for your bitcoin is a cup of soup. Bitcoins value has fallen and so has your purchasing power.

That’s why stable crypto coins were invented. They are meant to be stable relative to a real-world currency. USDC is a great example: 1 USDC tries to always be very, very close to 1 actual dollar. That means your steak would always have a stable price. 

Stable coins actually exist for many currencies and are actively used as payment methods. Another example, Celo Real, allows merchants in Brazil to accept payments from anyone in a coin that mimics their own currency, without either party having to have a bank account.

But beware! Often, stablecoins are not as stable as the name implies. Take our class to find out more!

What is a Stablecoin?

"TL;DR" stands for "too long; didn't read" and is often used as a tongue-in-cheek way to provide a summary of a longer piece of content up front. 

The term likely originated on social media and is now widely used across the web. Next time you come across TL;DR think about it this way: If you don't want to take the time to read, someone has already gone through the trouble of summarizing things. How nice is that?

What does TL;DR stand for?

To understand Web 3, let’s first talk about what got us here: Web 1 and Web 2

Web 1 refers to the early “read-only” web. Sites like Yahoo that served static content to you or businesses like Amazon that moved physical businesses to a web page.

Web 2 was when users like you started interacting with sites, creating internet-specific content. These were entirely new business concepts, like Facebook.

But there are problems: Companies need to make money for their shareholders and suddenly, you BECOME the product. They own YOUR content, and YOUR data, and can decide what they want to do with it. They have centralized control, even though YOU made them happen.

Web 3 turns that idea on its head: It decentralizes ownership and control. Imagine a new kind of Facebook: That project could issue a token instead of shares and users earn it for participating. And that token gives them the rights to vote on future plans. If things are going well, more people will buy that token, driving the price up. And if they decide it’s going the wrong way, they can just sell, driving the price down.

And because everything is on the blockchain, every decision and vote are public and fully transparent.

We just scratched the surface here, but we hope that gives you a general idea of Web 3 and why people are excited about it.


📖 Glossary

Understand complex concepts in easy ways

A

Altcoin

C

Crypto Wallet

F

Fork

H

HODL

M

Metamask

N

NFT

P

Proof of Work (PoW)

S

Stablecoin

T

TL;DR

W

Web3