Normal cryptocurrency is a code-based asset designed to work as an apparatus of exchange. Additional units can be added by mining. Everyone can participate if they've access to a computer. Mining requires a large amount of time and electrical power, though. A high-powered machine is also required, to mine profitably. On the other hand, Ripple is a centralised coin, which can't be mined. A finite amount of units were generated by the firm and this limit will never be exceeded.