What Is Cryptocurrency and How Does It Work?

Cryptocurrency is money that lives on a shared public record instead of inside a bank, and it works because thousands of independent computers keep identical copies of that record and constantly check each other. There is no head office. When you send bitcoin, you are not moving a file - you are asking the whole network to write a new line saying your balance went down and someone else's went up.

How does a payment actually happen?

Every account is a long address, like an email address made of letters and numbers, and each address has a secret key that only the owner holds. To pay someone you write the amount and their address, then sign it with your key. The signature proves the instruction came from you without revealing the key itself. Computers across the network check the signature, confirm you had the coins, and add the payment to the record a few seconds or minutes later. Bitcoin does this roughly every ten minutes; Ethereum does it about every twelve seconds.

What stops someone spending the same coin twice?

This was the problem nobody solved before Bitcoin, because a digital file can be copied endlessly. The answer is that nobody keeps their own balance - everyone keeps the same list. If you try to spend the same coin twice, the second attempt contradicts a line already written down in thousands of places at once, and the network rejects it. Changing history would mean rewriting those copies faster than the rest of the world adds to them, which is far too expensive to be worth attempting.

What do you actually own?

A key, not a coin. Your wallet - an app like MetaMask, or a small device like a Ledger - stores that key and nothing else. That is why there is no password reset: the network has no idea who you are, only whether a signature checks out. It is also why crypto comes in very different flavours. Bitcoin is deliberately simple digital money, Ethereum runs small programs so apps like Uniswap can swap tokens without a company in the middle, and Tether is designed to stay worth about one dollar for people who just want to move value.

If you try it, buy a small amount on a well-known exchange, move it to a wallet you control, and send a tiny test payment to yourself before sending anything that matters. Next, read what a blockchain is, or the same answer with fewer moving parts in cryptocurrency explained simply.