The blockchain technology that powers Bitcoin and many other cryptocurrencies is essentially a database, but it’s far different than any typical, centralized ledger. It’s decentralized and powered by peer-operated nodes distributed all around the world, with no supervising authority to call the shots or set the rules.
So how do you secure a decentralized network and ensure that everyone agrees on the contents of the ledger? That’s where Bitcoin’s proof of work consensus algorithm comes in.
In combination with public key cryptography, the proof of work consensus algorithm secures the distributed ledger and protects the network from “double spend” attacks, all while adding new blocks of transactions to the chain and generating BTC rewards.
The proof of work mechanism requires Bitcoin miners to compete to solve complex mathematical equations using their computers—a very energy-intensive process. It’s difficult on purpose, but the resulting Bitcoin rewards can be incredibly va
Źródło: https://decrypt.co/73344/what-is-proof-of-work-how-the-bitcoin-network-is-maintained
