Difficulty adjustment

In plain words

Miners constantly join, quit, and upgrade, so the network's total guessing power swings all the time. Every 2,016 blocks — about two weeks — every node re-tunes how hard the mining puzzle is, so blocks keep landing about every ten minutes. More miners? Harder puzzle. Miners leave? It eases. Like a thermostat, it keeps Bitcoin on schedule no matter how much power chases it.

Why it matters

• Keeps new coins on schedule no matter how many miners show up.
• Self-healing: after crashes or bans, the network rebalances itself.
• No committee sets it — every node computes the same number.

Go deeper

• Proof of work
• Hashrate
• The halving