ERC20

ERC-20 is the most widely used token standard on the Ethereum blockchain. It defines a set of rules and functions that a token smart contract must follow — such as how tokens are transferred, how balances are tracked, and how users can approve others to spend their tokens.

In simple terms, ERC-20 makes all Ethereum-based tokens interoperable, meaning they can easily work with wallets, exchanges, and decentralized apps (DApps). Every major crypto token built on Ethereum — from stablecoins like USDT and USDC to governance tokens and DeFi assets — follows the ERC-20 standard.

This video explains:

What ERC-20 is and why it matters.

The 6 key functions of ERC-20 (totalSupply, balanceOf, transfer, transferFrom, approve, allowance).

How ERC-20 ensures compatibility across DeFi platforms.

The difference between ERC-20 and other standards like ERC-721 (NFTs) or ERC-1155.

Security best practices and common issues (reentrancy, approval race conditions).

By the end, you’ll understand how most tokens work under the hood — and why ERC-20 remains the backbone of Ethereum’s ecosystem.

Tip: Before investing in any new token, always check if it’s ERC-20 compliant and verified on Etherscan.