Altcoins are cryptocurrencies other than bitcoin. Many altcoins are forks (variations) of bitcoin.
“Altcoin” is a combination of two words: “alt” and “coin”. The word “alt” is short for alternative and “coin” means currency.
This nomenclature comes from the idea that bitcoin is the original cryptocurrency and that all others are then considered “alternate” or “alternative” coins. Together, they imply cryptocurrencies that are an alternative to the original cryptocurrency named bitcoin.
Many altcoins have emerged but bitcoin still remains the largest and most popular of all cryptocurrencies.
The term “altcoin” is also used quite broadly to refer to digital assets that would also technically be referred to as “tokens” rather than coins.
The best-known examples are the ERC-20 tokens that exist on top of the Ethereum blockchain. Since the creation of Bitcoin in 2008, more than 2,000 alternative cryptocurrencies were deployed.
Many of these altcoins were created as modified copies of Bitcoin, through a process known as Hard Fork. Despite sharing some similarities, each altcoin has its own functionalities.