Plain English
A blockchain is a shared digital record book that anyone can read but no single party controls. New entries (called blocks) are added in order, and each block is cryptographically linked to the one before it. To alter a past entry, you would have to rebuild every block that came after — which the network would reject.
How it actually works
Each block contains a list of transactions, a timestamp, and the cryptographic hash of the previous block. That hash is what creates the “chain.” The network agrees on which chain is valid via a consensus mechanism (proof-of-work for Bitcoin, proof-of-stake for Ethereum and most modern chains).
Anyone can run a node and download the entire ledger. There is no master copy. The ledger’s integrity does not depend on trusting any single party.
What it means for you
The blockchain is what makes cryptocurrency possible. It is also what makes ownership verifiable, transfers irreversible, and counterparty trust unnecessary for the basic mechanics. Every strategy in our curriculum sits on top of this foundation.
You will leave the curriculum with a working mental model of how the major blockchains differ — throughput, finality, security assumptions — and how those differences should drive your allocation and custody choices.
Educational content only. Not investment, tax, or legal advice.