What Is an Altcoin?
Altcoins are generally defined as all cryptocurrencies other than Bitcoin (BTC). However, some people consider altcoins to be all cryptocurrencies other than Bitcoin and Ethereum (ETH) because most cryptocurrencies are forked from one of the two. Some altcoins use different consensus mechanisms to validate transactions, open new blocks, or attempt to distinguish themselves from Bitcoin and Ethereum by providing new or additional capabilities or purposes.