Difficulty (Mining)
Bitcoin's self-adjusting dial that keeps blocks arriving every ~10 minutes no matter how much mining power joins or leaves.
Difficulty measures how hard it is to find a valid block in Proof of Work mining. Bitcoin re-targets it every 2,016 blocks (~two weeks): if blocks arrived faster than 10 minutes on average, difficulty rises; slower, it falls. This feedback loop is why block times stay stable whether the network has a thousand miners or a million.
Difficulty is also a confidence gauge: it rises when miners invest in new hardware and falls during capitulations (China’s 2021 mining ban cut it ~28%, the largest drop ever, before full recovery). All-time-high difficulty means more real-world capital is defending the ledger than ever.