ERC-20 (Ethereum Request for Comment 20) is a homogeneous token created using smart contracts on Ethereum (Fungible Token) is a set of technical standards/rules, which is essentially a set of smart contracts.

What is a homogeneous certificate? What is a smart contract? Please refer to the chapters "What is a Fungible Token" and "What is a Smart Contract".

The core feature of ERC-20 is that Tokens are more convenient to trade under its standards. If developers want their smart contract tokens to be Swapable on Ethereum, their contract tokens must comply with this standard.

In addition to basic information such as name Symbol, the following functions meet the minimum requirements of ERC-20:

• TotalSupply: This token The maximum issuance (that is, Max Supply)
• BalanceOf: can record the currency balance of the currency holding address
• Transfer : Supports automatic transfer of specific amounts to specific addresses. (TransferFrom)
• TransferFrom: Supports automatic transfer of a specific amount to a specific address. (Transfer)
• Approve: Allow a specific other address/contract/Spender address to withdraw a specific number of tokens from a specific account. (Withdrawal with upper limit)
• Allowance: Let other addresses/contracts/Spenders return the money withdrawn to the Owner
• Transfer (Event ): When a Transfer is successful, a Transfer (Event) will be triggered
• Approval (Event): When the Owner authorizes other addresses/contracts/Spenders to Approval (Event) will be triggered when the above functions such as Approve and Allowance are completed.

The token with ERC-20 as the unified standard is recorded in the smart contract and basically meets the functions of currency in the traditional sense: it contains 8 important basic fields such as TotalSupply (recognized, Limited quantity), can record the holder's address (clear ownership), and can be transferred and traded between smart contracts with different functions (universal tradability).

History

In 2015, engineer Fabin Vogelstellar submitted an Ethereum Request Comment (Ethereum’s technical standard document to facilitate developers from all over the world to develop using unified standards) on Github, no. For 20, which is later known as the ERC-20 document, it provides standards for developing and creating homogeneous tokens in Ethereum smart contracts, including name, symbol, maximum amount, balance, transfer, source, permission and other fields. , opening the era of standardized tokens.

Following the process used by the Ethereum developer community, the proposal was approved and implemented in 2017 as Ethereum Improvement Proposal 20 (EIP-20).

You may also be interested in:

• What is an EIP?
• What are NFTs?