Intro to Blockchain: How It Works and Why It Matters
Free intro to blockchain: blocks, hashes, keys, transactions, consensus, smart contracts, and how to evaluate any protocol.
About this course
Blockchain is everywhere—but how does it actually work?
This free course is your complete introduction to blockchain fundamentals. No hype, no marketing, no prerequisites. You’ll learn what a blockchain is, why it’s different from a database, and how it actually solves problems.
Over 7 modules and 25 lessons, you’ll:
– Understand blocks, hashes, and cryptographic linking
– Learn how public and private keys work and why they matter
– Trace a real transaction from wallet to confirmation
– Compare Proof of Work and Proof of Stake
– Explore smart contracts and tokens
– Read a block explorer and find real on-chain data
– Evaluate any blockchain protocol using a repeatable framework
Each lesson includes a worked example and a hands-on exercise. You’ll quiz yourself after each module and complete a capstone project analyzing a real blockchain.
By the end, you’ll have the foundation to understand any blockchain conversation—and you’ll know whether to go deeper into Solidity, staking, or DeFi.
Start free. Go as deep as you want.
What you will be able to do
- Can explain what a blockchain is and why it's different from a database
- Can describe how blocks, hashes, and cryptographic linking create immutability
- Can explain public/private keys and why they matter for ownership
- Can trace a transaction from wallet to confirmation and calculate fees
- Can compare PoW and PoS consensus and explain why consensus matters
- Can describe what a smart contract is and how tokens work on-chain
- Can read a block explorer and find real transaction data
- Can evaluate any blockchain protocol using a repeatable framework
Curriculum
1What Is Blockchain?
2Blocks, Hashes, and Cryptography
3Keys, Wallets, and Ownership
4Transactions and Fees
5Consensus and Security
6Smart Contracts and Tokens
7Capstone u2014 Evaluate a Protocol
Taught by Block Relations
Research & Education · Built for a curious beginner with no crypto or technical background who wants to understand what blockchain is, how it actually works (not marketing), and whether it matters to them.
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