altcoin is any cryptocurrency other than Bitcoin. The term generally refers to any coin that is built on a different protocol than Bitcoin, such as Litecoin, Ethereum, or Monero.
There are hundreds of altcoins in existence, and new ones are created every day. While some altcoins are simply clones of Bitcoin with minor changes, others offer major improvements over the original coin.
While Bitcoin remains the biggest and most well-known cryptocurrency, altcoins are gaining ground and beginning to challenge Bitcoin’s dominance. Ethereum, for example, is the second largest altcoin by market capitalization, and it offers a number of advantages over Bitcoin, including faster transaction speeds and lower fees. As the cryptocurrency market continues to evolve, altcoins are likely to play an increasingly important role.