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Ethereum & Smart Contracts with Solidity Course

Write, test, and deploy EVM smart contracts. Cover ERC-20 tokens, events, gas optimization, and interacting from JavaScript using ethers.js. Follow this…

Course overview

Write, test, and deploy EVM smart contracts. Cover ERC-20 tokens, events, gas optimization, and interacting from JavaScript using ethers.js.

Ethereum Account Model vs Bitcoin UTXO

Ethereum uses an account model instead of UTXOs: EOAs (Externally Owned Accounts): held by private keys — send transactions Contract Accounts: code stored on-chain, executed by the EVM when called Key differences from Bitcoin: Gas: every operation costs ETH (prevents infinite loops) State: contracts persist variables on-chain across calls Programmability: Turing-complete Solidity runs complex logic

Write an ERC-20 Token in Solidity

ERC-20 is the standard fungible token interface. Here's a minimal implementation using OpenZeppelin.

Interact with Smart Contracts using ethers.js

ethers.js is the most popular JavaScript library for Ethereum — reading state, sending transactions, and listening to events.