Lesson 4: The shared list everyone can check — Baskin Logic Crypto Academy

A blockchain is a shared ledger. Many machines keep the same list of records.

Each new record points at the one before it. That chain is the history. Nobody in this room is being sold a chain. The object is the list.

A classroom in Medellín and a classroom in Miami can read the same public list. The school does not tell you what to buy.

Key terms

Blockchain: A blockchain is a shared record of transactions that many computers keep at the same time.
How blockchain works: A blockchain works in a loop.
Node: A node is a computer that runs a blockchain's software and keeps a copy of its record.
Crypto vs. blockchain: A blockchain is the technology: a shared record kept by many computers.
Cryptocurrency: A cryptocurrency is digital money that is sent and recorded on a blockchain instead of through a bank.

Five questions from this lesson. Your score stays on this device.

Show the answers

A shared ledger. A blockchain is a shared ledger, one list of records kept by many machines.
Many machines that keep the same list. Many machines keep the same list of records.
The one before it. Each new record points at the one before it. That chain is the history.
Yes. A public blockchain is the same list for anyone who reads it.
It would no longer match everyone else's copy. A changed copy would not match the many other copies, so the change stands out.

Written and reviewed by Joshua Baskin, founder. Last reviewed October 2, 2026. How we check facts · Report an error

This lesson explains a basic idea and does not quote outside figures. Terms follow our glossary, and rule pages link to the official text.