Standard crypto-coins are a code-based resource built to work as a medium of trade. Additional coins are added via mining. Any person is able to participate if they've access to a computer. Mining requires a lot of hours and electrical power, though. A fast machine is also required, to do this profitably. However, Ripple is a centralised coin, which is unmineable. A fixed amount of coins were generated by the firm and this limit will never be exceeded.