What is a Bitcoin miner?
A computer, or a pool of them, that bundles waiting transactions into blocks and secures the network, paid in new bitcoin and fees.
Miners race to find a block whose fingerprint, its hash, is small enough. It takes enormous trial and error, and that work is what makes rewriting Bitcoin's history so costly.
The winner earns the block rewardBlock rewardWhat a block's miner earns: new bitcoin from the subsidy, plus the fees of every transaction in the block.: new bitcoin, plus the fees of the payments it included. Most miners join pools that share the work and the rewards.