Web3 Academy — Learn Blockchain, Solidity & DeFi

ERC-20 defines a standard interface for fungible tokens on Ethereum. Required functions: totalSupply(), balanceOf(address), transfer(to, amount), approve(spender, amount), transferFrom(from, to, amount), and allowance(owner, spender). Required events: Transfer and Approval. Using OpenZeppelin's battle-tested implementation is recommended over writing your own. Extensions include ERC-20Permit (gasless approvals via signatures) and ERC-20Votes (governance support).

💡 Key Takeaway

This lesson covers the fundamental concepts. Make sure you understand these before moving to the next chapter.

ERC-20 Token Standard