Blockchain & Web3
How blockchains work, from hashing and blocks to smart contracts, tokens, NFTs and DeFi. Build a toy blockchain in Python.
Every lesson runs real code in your browser, checked the moment you submit. No installing anything, no setup, no waiting.
Start Blockchain & Web3 freeWhat this course covers
- What is a Blockchain?
- Hashing: Digital Fingerprints
- Blocks and the Chain
- Tamper-Evidence: Why It's Secure
- Merkle Trees
- Keys and Wallets
- Elliptic-Curve Cryptography and Digital Signatures
- Transactions and Signing
- Consensus: How Nodes Agree
- Proof of Work and Mining
- Proof of Stake and Beyond
- Build a Toy Blockchain
- Bitcoin: The First Blockchain
- The UTXO Model: How Bitcoin Tracks Value
- Ethereum and the EVM
- Smart Contracts
- Solidity Basics
- ERC-20 Tokens
- NFTs (ERC-721)
- DeFi Building Blocks: Pools, Lending, and Stablecoins
- DeFi: Decentralized Finance
- dApps and Web3
- Security, Scams and Scaling
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