Crypto, From Scratch

No prior crypto knowledge. By the end you'll know what a blockchain is, who really owns a wallet, and where your fee goes.

What a blockchain actually is — blocks, hashes and chains; keys, wallets and signatures; how transactions and fees work; and why Bitcoin and Ethereum track your money in two completely different ways.

Everyone has heard the word blockchain; far fewer can say what one actually is. This topic fixes that from zero — no finance background, no computer-science degree, no assumption that you’ve ever owned a coin.

We build it as a ladder, one rung at a time:

The chain itself — blocks, hashes, and why tampering with old history is effectively impossible.
Keys and wallets — the public/private key pair that is your identity, and the seed phrase that backs it up.
Wallets without storage — how a “wallet” can hold money it never actually stores.
A transaction’s journey — from your screen to the mempool to a confirmed block in the seconds after you hit send.
The fee — what it really buys: a seat in the next block.
UTXO vs. account — Bitcoin’s model of digital coins versus Ethereum’s model of running balances.

Get these and every later crypto and DeFi topic stops being jargon and starts being mechanics.

In this topic