ERC-20

Definition

ERC-20 is an Ethereum token interface standard for fungible assets, meaning units within a particular token are treated as interchangeable. It specifies common functions and events for balances, transfers, total supply, and allowances that let another address spend an approved amount. This shared interface helps wallets, exchanges, and applications interact with many different tokens using similar software. It does not require a particular business model, fixed supply, market price, or governance arrangement. Some familiar metadata fields, including a token's name, symbol, and decimal precision, are optional in the original specification. Decimals affect display conventions rather than creating fractional arithmetic inside the token's integer balances. Implementations can add minting privileges, transfer restrictions, or other behavior, so interface compatibility is not a security certificate. Users should verify the contract address and understand approvals rather than relying only on a familiar ticker symbol.