Cryptocurrency - Altcoins
Altcoins in relation to cryptocurrency are any other coins that aren't bitcoin. The biggest one of these is Ether, the coin of the Ethereum network. Sometimes said to be the Silver to Bitcoin's Gold, that is actually a poor analogy. Ether is more of a currency that Bitcoin is, but it's capabilities are almost endless. The technology that the Ethereum network utilizes is far more advanced than bitcoin. Things you can do on the Ethereum network are smart contracts, creation of new tokens and NFTs.