---
# System prepended metadata

title: Blockchain

---

# Blockchain

A collaborative database secured by math and cryptography.

New records are sent to many computers. These computers must agree on the records before adding them to the database.

Records are added in groups called blocks. Each block links to the previous one, creating a chain of blocks, or a blockchain.

```mermaid
graph RL
    D[Current Block] --> C[Block 2]
    C --> B[Block 1]
    B --> A[Genesis Block]
```

This model of recordkeeping is complementary to that of the Internet, a network of computers that contain their own public and privately accessible files and data.

## Bitcoin

Bitcoin, the first blockchain, was made as a response to the 2008 financial crisis. It is a digital currency built atop a blockchain as a public ledger to record transactions.