What is ethers.js?

ethers.js is a modern, complete Ethereum JavaScript library that is the de facto standard for new Web3 development, largely replacing web3.js. Created by Richard Moore in 2016. Advantages over web3.js: (1) Smaller bundle — ~88KB vs web3.js ~1MB+; (2) TypeScript native — full TypeScript types built-in; (3) Cleaner API — provider/signer separation is more intuitive; (4) BigNumber handling — v6 uses native BigInt; (5) Better testing — widely used with Hardhat and Foundry. Key components: Provider — read-only Ethereum connection: const provider = new ethers.JsonRpcProvider("https://eth-mainnet.g.alchemy.com/v2/KEY"); Signer — account that can sign transactions: const signer = await provider.getSigner(); Contract — interface to smart contract: const contract = new ethers.Contract(address, abi, signerOrProvider). Call view function: const balance = await contract.balanceOf(address). Send transaction: const tx = await contract.transfer(to, amount); await tx.wait(). Ethers v6 (2023) introduced significant API changes from v5.