A token standard is a set of rules – enshrined by a smart contract – that allow an asset to be created on a blockchain.
Token standards are unique to each blockchain. Some of the most popular standards include ERC-721 on Ethereum, SPL on Solana, and BRC-20 on Bitcoin. These all allow for NFTs (or their equivalent) to be minted on their associated blockchains.
Token standards aren’t just for NFTs – they can allow cryptocurrency tokens to be created on a blockchain too. ERC-20 is the most popular crypto token standard on Ethereum, which is behind the likes of USDT, ApeCoin (APE), and ETH itself.