Proof of Work (PoW) is a consensus algorithm used in blockchain technology to secure and validate transactions on the network. The PoW algorithm requires network participants, known as miners, to solve complex mathematical problems to add new blocks to the blockchain. The miner who successfully solves the problem is rewarded with newly minted cryptocurrency as well as transaction fees.
The PoW algorithm is computationally intensive and requires a significant amount of computing power and energy consumption, which has led to criticism over its environmental impact. However, it remains the most widely used consensus algorithm in cryptocurrencies such as Bitcoin and Ethereum.