ERC-20 stands for Ethereum Request for Comment 20 and is the standard used for creating fungible tokens on the Ethereum blockchain. It provides guidelines for creating new tokens so that they can be easily interchanged with other tokens used within smart contracts. Fungible tokens are those that have identical properties and can be used interchangeably with each other. ERC-20 tokens are used in many applications, including initial coin offerings (ICOs) and decentralised finance (DeFi) projects