At the heart of every cryptocurrency is an equation. That equation is what lets the blockchain exist. It determines the validity of each block, and is the reason that blockchain-based transactions are so secure; you can’t fake anything because it has to agree to the equation. Mining is the act of solving that equation. Once a person solves a problem, he or she gets a coin. Anyone can do it, but it’s also time-intensive and requires a computer to do it efficiently.