Bitcoin
How Does the Network Agree on the Truth?
How does Bitcoin agree on the truth without a central authority? Through Proof-of-Work, mining, and economic incentives that make the blockchain effectively immutable.
Bitcoin
How Does Bitcoin Record Transactions?
From signed transactions to blocks to the blockchain. How Bitcoin creates a tamper-evident record of every transfer ever made.
Bitcoin
How Does Bitcoin Use Cryptography?
Hash functions and key pairs: the two cryptographic foundations that make Bitcoin secure. Explained without math, using examples you can verify yourself.
Bitcoin
Why Was Bitcoin Created?
Bitcoin emerged during the 2008 financial crisis. It solved a problem that decades of research could not: how to transfer value digitally without trusting any institution.
Bitcoin
What Is Bitcoin?
Bitcoin is both a new form of money and a new kind of monetary system. Two definitions that explain what makes it different from anything that came before.
Smart Contract
Smart Contracts 04: Deployment
Deploy the InteractionLogger smart contract to a local Hardhat node and to Arbitrum Sepolia, verify it on Arbiscan, and interact with it via console and blockchain explorer.
Smart Contract
Smart Contracts 03: Testing
Write a complete TypeScript test suite for the InteractionLogger smart contract using Hardhat, Ethers, Mocha, and Chai - covering happy paths, emitted events, and custom error reverts.
Smart Contract
Smart Contracts 02: Development
Build the InteractionLogger smart contract from scratch in Solidity. Learn how to use structs, mappings, events, custom errors, and validation logic - section by section with full code and explanations.
Smart Contract
Smart Contracts 01: Setup
Install Node.js, VS Code and MetaMask, create a test wallet, get SepoliaETH, and bridge it to Arbitrum Sepolia - everything you need before writing your first smart contract.