Cryptocurrency is a form of digital money that runs on decentralized networks called blockchains. Unlike traditional currencies issued by governments, most cryptocurrencies are not controlled by any single company or central bank. Instead, transactions are verified by a global network of computers and recorded on a public ledger that anyone can inspect.
How does cryptocurrency work?
At its core, a blockchain is a shared database that stores every transaction in linked "blocks." When you send crypto, the network confirms that you own the coins and updates everyone's copy of the ledger. This design makes the records very difficult to tamper with and removes the need for a middleman like a bank.
Bitcoin, Ethereum and "altcoins"
Bitcoin (BTC) was the first cryptocurrency, launched in 2009, and remains the largest by market value. Ethereum (ETH) introduced "smart contracts" — self-executing programs that power applications, tokens and decentralized finance. Every other coin is informally called an "altcoin," and there are tens of thousands of them. You can browse the full list of live prices on our homepage.
Key terms to know
- Market cap — the total value of all coins in circulation (price × circulating supply).
- Volume — how much of a coin was traded in the last 24 hours.
- Wallet — software or hardware that stores the keys used to access your crypto.
- Supply — how many coins exist now and the maximum that will ever exist.
We explain these in more detail in our guide on how to read crypto prices.
Is cryptocurrency risky?
Yes. Crypto prices are highly volatile and can rise or fall sharply in a short time. Never invest more than you can afford to lose, and always do your own research before making any decision. Nothing on this website is financial advice.