Cryptocurrency is a form of digital currency secured through cryptography, which makes it nearly impossible to counterfeit or double-spend. Cryptocurrencies use decentralized control as opposed to centralized digital currency and central banking systems. Transactions are recorded on a public ledger called a blockchain, and new units of a particular cryptocurrency are created through a process known as mining. In order to mine a cryptocurrency, powerful computer hardware is required and the miner must be rewarded with units of the cryptocurrency (coins or tokens). The process also verifies and records any transaction made with the currency.