What are alt-coins?

Alt-coins is a collective name for all digital coins that are not Bitcoin.

Besides Bitcoin, there are thousands of other forms of cryptographic money that serve as alternatives to Bitcoin, hence the name alt-coins. Well-known examples of alt-coins are Ethereum (ETH), but there are also many others such as Einsteinium, Groestelcoin and BanaBit.

Because the issuance and trading of digital coins are (largely) unregulated, it is difficult to obtain exact data on their scope. Furthermore, new coins are constantly in circulation (mining) and the prices often show enormous fluctuations.