Miner

Definition
A miner is

"an individual or entity that participates in a decentralized virtual currency network by running special software to solve complex algorithms in a distributed proof-of-work or other distributed proof system used to validate transactions in the virtual currency system."

Overview
"Miners may be users, if they self-generate a convertible virtual currency solely for their own purposes, e.g., to hold for investment or to use to pay an existing obligation or to purchase goods and services. Miners may also participate in a virtual currency system as exchangers, creating the virtual currency as a business in order to sell it for fiat currency or other virtual currency."