What Is a Blockchain?

Where it came from, what it does, and how you make one

Photo: LuckyStep48/Getty Images

What is it?

A public¹, permanent², append-only³ distributed⁴ ledger⁵.

  1. Though some blockchains require permission to access, “open” blockchains like those underlying Bitcoin and Ethereum are accessible to anyone, meaning the database is public information

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MIT Technology Review

MIT Technology Review

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