Blockchain Fundamentals: How Crypto Actually Works

About this course

You’ve heard about blockchain, Bitcoin, Ethereum, and Layer 2s. But do you really understand how they work?

This course teaches the ground-up fundamentals every finance professional, tech leader, and investor needs before they put money or credibility behind a protocol. You’ll start with the cryptographic primitives — hash functions, digital signatures, and key derivation — that make a blockchain tamper-evident and self-custodied in the first place. From there you’ll compare Bitcoin’s UTXO model against Ethereum’s account model, trace a transaction from wallet to mempool to miner, and see exactly what a block header contains and why.

The consensus module breaks down Proof-of-Work and Proof-of-Stake side by side — not as slogans, but as concrete trade-offs in security, decentralization, and speed — and explains why a transaction needs confirmations before it’s considered final. From there you’ll learn to actually read a block explorer: decoding gas, fees, contract calls, and following addresses on-chain, so a block explorer stops being a wall of hex and starts being a source of answers.

A full module is dedicated to fees and economics: how Ethereum gas actually works, what EIP-1559 changed, why Layer-2 rollups are cheaper, and how to compare total cost of ownership across Bitcoin, Ethereum, and L2s. Another covers bridges and wrapped tokens — how assets move across chains, and the custody and security trade-offs that have caused some of crypto’s largest hacks. The final content module covers custody and security hands-on: self-custody vs. exchange custody, hardware wallets and mnemonics, phishing and signing hygiene, and a repeatable rubric for evaluating any blockchain protocol on its own merits.

By the end, you’ll be able to explain hashing and signatures to a colleague, calculate and compare gas costs across chains, assess a bridge’s security model before trusting it, and apply a standard rubric to any protocol — Bitcoin, Ethereum, Solana, Polygon, or whatever comes next — rather than relying on hype or headlines.

28 lessons across 8 modules, module quizzes, a capstone project where you analyze a real protocol against the course rubric, downloadable cheat sheets per module, and a certificate on completion. No hype. Just how blockchains actually work.