Lesson 4 · Literacy path

The shared list everyone can check

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Baskin Logic Crypto Academy. One idea. Then we stop.

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.

A candle, an old key-shaped magnifier and a map on a dark table

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.

Check what you learned

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

1. What is a blockchain?

2. Who keeps the list?

3. What does each new record point at?

4. Can a classroom in Miami and one in Medellín read the same public list?

5. Why is it hard to cheat by changing an old record?

Show the answers
  1. A shared ledger. A blockchain is a shared ledger, one list of records kept by many machines.
  2. Many machines that keep the same list. Many machines keep the same list of records.
  3. The one before it. Each new record points at the one before it. That chain is the history.
  4. Yes. A public blockchain is the same list for anyone who reads it.
  5. It would no longer match everyone else's copy. A changed copy would not match the many other copies, so the change stands out.
Literacy · Up nextNext: Lesson 5 — What a transaction is

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