BEP20 is an extension of the previous BEP2 standard (used on Binance Chain). It is designed to improve compatibility with Ethereum tokens and provide additional features, such as lower transaction fees and faster confirmations due to the higher throughput of the BSC. The main difference between ERC20 and BEP20 is the blockchain they run on: ERC20 is the standard for Ethereum, while BEP20 is for Binance Smart Chain. This difference in blockchains determines the speed of transactions, fees, and overall user experience. Thus, the choice between BEP20 and ERC20 depends on the needs of users and developers, as well as the goals and requirements of the project.