Web3 & Blockchain

What is Proof of Work?

Quick answer

A blockchain consensus mechanism in which miners compete to solve computational puzzles to add new blocks and secure the network.

Proof of Work, explained

Proof of work was popularized by Bitcoin. Miners repeatedly hash block data with different random values until they find a result below a target set by the network. Finding this answer takes enormous trial and error, but checking it is easy for everyone else. The winning miner adds the block and receives a reward.

This design makes rewriting history extremely costly, because an attacker would need to redo the work faster than the rest of the network combined, which is why a 51 percent attack is considered the main theoretical threat. The main criticism of proof of work is its large electricity consumption and the specialized hardware it requires. Supporters argue the energy cost is what provides security.

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