Learn crypto
55 guides, each starting with a short answer you can read in 20 seconds, then going as deep as you like.
Start with the free course
Crypto basics
What is cryptocurrency?Cryptocurrency is digital money that isn't issued by a bank or government.Cryptocurrency, beyond the hypeCryptocurrency is a shared record of who owns what, kept by thousands of computers that follow the same rules instead of one bank.List of cryptocurrenciesThe best-known cryptocurrencies include Bitcoin (2009), Litecoin (2011), XRP (2012), Dogecoin (2013), Ethereum (2015), the stablecoins Tether (USDT) and USD Coin (USDC), and newer networks such as Cardano, Solana, Avalanche and Polkadot.How does cryptocurrency work?You sign a transaction with your private key.What is a blockchain?A blockchain is a record of transactions grouped into blocks, where each block contains a fingerprint (a hash) of the one before it.Coin vs. tokenA coin is the native currency of its own blockchain, like BTC on Bitcoin or ETH on Ethereum.How many cryptocurrencies are there?It depends what you count.Is crypto dead?No.
Bitcoin
What is Bitcoin?Bitcoin is the first cryptocurrency: digital money with no company or government in charge, launched in 2009.Who created Bitcoin? The Satoshi Nakamoto storyBitcoin was created by Satoshi Nakamoto, a pseudonym for a person or group whose real identity is unknown.What is crypto mining?Crypto mining is the process of using computers to add new blocks of transactions to a proof-of-work blockchain like Bitcoin.What does a bitcoin look like?A bitcoin doesn't look like anything: it has no physical form.Bitcoin Pizza Day: the 10,000 bitcoin pizzasOn May 22, 2010, Florida programmer Laszlo Hanyecz paid 10,000 bitcoins to have two Papa John's pizzas delivered, one of the first known purchases of real goods with bitcoin.
Ethereum and other networks
What is Ethereum?Ethereum is a blockchain that can run programs called smart contracts, which power tokens, stablecoins, trading apps and more.Who created Ethereum? Vitalik ButerinEthereum was proposed by Vitalik Buterin, a Russian-Canadian programmer, in a white paper in late 2013, when he was 19.What is Ethereum Classic?Ethereum Classic (ETC) is the original Ethereum blockchain that continued after the 2016 "DAO" hack, when most of the community chose to rewrite history to return stolen funds.What is ENS (.eth names)?ENS, the Ethereum Name Service, lets you register a readable name such as alice.eth and point it at your wallet address, like a domain name for crypto.What is Litecoin?Litecoin (LTC) is a cryptocurrency launched in October 2011 by former Google engineer Charlie Lee, based on Bitcoin's code.What is a stablecoin?A stablecoin is a cryptocurrency designed to stay at a fixed value, usually $1.What is an NFT?NFT stands for non-fungible token: a unique token on a blockchain that records who owns a specific item, usually a digital image, collectible or membership.What is a smart contract?A smart contract is a program stored on a blockchain that runs automatically when its conditions are met, for example swapping one token for another or releasing a loan.What are layer 2 networks?A layer 2 is a separate network that processes transactions cheaply and quickly, then posts a summary back to a main blockchain (layer 1) such as Ethereum, borrowing its security.What is proof of work?Proof of work is how Bitcoin decides who adds the next block.What is proof of stake?In proof of stake, validators lock up (stake) the network's coin as a deposit.
Wallets and sending
What is a crypto wallet?A crypto wallet, also called a blockchain wallet, is an app or device that stores the private keys controlling your crypto.Custodial vs. non-custodial walletsWith a custodial wallet, a company such as an exchange holds the keys to your crypto and you log in with a password.What is MetaMask?MetaMask is a free self-custody crypto wallet, available as a browser extension and a phone app, mainly for Ethereum and compatible networks, plus Solana and Bitcoin.What is a hardware wallet?A hardware wallet is a small device, often like a USB stick, that stores your private keys offline and signs transactions inside the device.Public key vs. private keyYour private key is a secret number that lets you spend your crypto; never share it.What is a seed phrase?A seed phrase (also called a recovery phrase or secret recovery phrase) is a list of 12 or 24 ordinary words that your wallet creates.What happens when you send crypto?When you press send, your wallet signs the transaction and broadcasts it.How to look up a crypto transactionA block explorer is a free website that shows everything on a blockchain.Crypto transaction fees explainedWhen you buy or send crypto you may pay several fees: a network fee to the miners or validators who process the transaction, a trading fee to the exchange, a spread (the gap between buy and sell prices), and sometimes a withdrawal fee.
Buying and money
What is a crypto exchange?A crypto exchange is a platform where you buy, sell and swap cryptocurrency.How to buy Bitcoin safelyThe safest way for most beginners is to buy a small amount through a well-known, regulated exchange or brokerage you reach by typing its address yourself, secure the account with app-based two-factor authentication, and move larger long-term holdings to a wallet you control.How to buy EthereumBuy ETH through a reputable, regulated exchange or app you reach directly, secure your account with app-based two-factor authentication, and if you move it to your own wallet, choose the network carefully: ETH on Ethereum and ETH on a layer 2 like Base or Arbitrum are on different networks.How to calculate crypto profitProfit = what you received when you sold (after the sale fee) − what you paid in total (including the purchase fee).How to find your crypto break-even priceYour break-even price is the selling price at which you'd get back exactly what you spent.Crypto vs. stocks and ETFsA stock is a legal share of a company, with a claim on its profits and rights as an owner.Crypto staking and yield, explainedStaking means locking up coins to help run a proof-of-stake network in return for rewards.Crypto taxes: the basics (US)In the US, the IRS treats crypto as property.
Markets and trading
Crypto market cap explainedMarket cap is a coin's price multiplied by the number of coins in circulation.How to read a crypto chartA crypto chart shows past prices over time.How to research a cryptocurrencyInstead of asking whether a coin's price will go up, ask what it does, who controls it, how many coins exist and who holds them, whether people actually use it, whether it's been hacked, and whether you could sell it.Why is crypto going down, and will it go back up?Crypto usually falls when investors turn cautious: rising interest rates, bad news, big holders selling, or traders who borrowed money being forced to sell.Will Bitcoin hit $1 million?Nobody knows.Can you day trade crypto?Yes.Paying for crypto: card, Apple Pay or bank transfer?A bank transfer is usually the cheapest way to buy crypto.
Going deeper
Is crypto anonymous?No.What is a CBDC (digital dollar)?A CBDC (central bank digital currency) is a digital form of a country's money issued directly by its central bank, like a digital dollar or digital euro.Types of bitcoin: BTC and the look-alikesThere's one original Bitcoin, ticker BTC.How to create a cryptocurrencyThere are two ways: build a whole new blockchain with its own coin (a huge software and security project), or create a token on an existing blockchain like Ethereum or Solana, which can take minutes and a small network fee.
Safety
Before you send crypto: the safety pauseBefore you send crypto or approve anything in your wallet, stop and check: is anyone rushing you, did you reach the site yourself, are the coin, network, address and amount right, what permission are you granting, and is anyone asking for your seed phrase? If anything feels unclear, don't approve it yet.Crypto scams: how to spot themCrypto scams usually rely on persuasion rather than hacking: someone builds trust or creates panic, then gets you to send crypto, buy it at an ATM, or reveal your seed phrase.Sent crypto to the wrong network?If you sent crypto on the wrong network but to an address you or an exchange control, it can often be recovered, sometimes by contacting the exchange.