What Are Altcoins? Coins Other Than Bitcoin, Explained

An altcoin is any cryptocurrency that is not Bitcoin. The word is short for "alternative coin", and it stretches from Ethereum, the second-largest network, through Solana, XRP, Cardano and Dogecoin, down to thousands of tokens nobody has heard of. Some are serious infrastructure that millions of people use. Many are experiments, and a good number have been quietly abandoned.

Why do altcoins exist at all?

Because Bitcoin was designed to do one job well — move and store money on a network nobody controls — and it is deliberately hard to change. Other projects wanted different trade-offs. Ethereum added smart contracts, small programs that run on the network itself, which is what makes apps such as Uniswap and Aave possible. Solana gave up some decentralization in exchange for speed and fees measured in fractions of a cent. Stablecoins like Tether are altcoins with a plain job: stay worth about a dollar, so people can send dollars over the internet. Dogecoin began as a joke about crypto and stayed popular anyway.

Are altcoins riskier than Bitcoin?

Structurally yes, and it helps to know why rather than just be told so. They are smaller, so there are fewer buyers when everyone heads for the exit at once and the swings are sharper in both directions. Many have a company or foundation that can issue more coins or change the rules. Most run on far fewer independent computers. And the record is unforgiving: of the thousands of coins launched over the past decade, the large majority now barely trade at all.

How do you look at one before buying?

Ask what it does that an existing network cannot, and whether anyone actually uses it — real activity, not follower counts. Look at who holds the supply, because a coin whose team kept most of it can be sold on top of you. Check that the code is public and that the project has been running long enough to have been attacked and survived. Be most suspicious of coins that arrive in your messages: an unsolicited tip is a sales pitch, and frequently a trap.

If you do buy one, get the token's address from the project's own site rather than from a search result or a reply, because fake copies of popular tokens are everywhere. Then move it to a wallet you control instead of leaving it on the exchange. Read next: what decentralization means and why the network effect matters.