Plain English
Proof of Work is the original blockchain consensus mechanism — Bitcoin’s. Miners compete to solve a cryptographic puzzle; the first to find a valid solution proposes the next block and earns the reward.
How it actually works
Miners hash block data billions of times per second searching for an output below a target. Finding one is probabilistic and requires real computational work. The network adjusts difficulty every ~2 weeks to keep block times constant. Energy consumption is high — and is, structurally, the security cost. To attack a PoW chain you would need to outcompute the entire honest miner network.
What it means for you
For Bitcoin holders, proof-of-work is the security model. The energy expenditure is not a bug — it is the structural cost that makes Bitcoin’s ledger expensive to attack.
We teach proof-of-work as Bitcoin’s defining feature and the structural reason the BTC supply schedule is credible. Contrasted with proof-of-stake economics, the differences matter for portfolio construction.
Educational content only. Not investment, tax, or legal advice.