Centralised cryptocurrency is a code-based holding designed to be used as an item of exchange. Additional units can be created via mining. Any person can participate if they've access to a computer. Mining requires a great deal of time and electricity, though. A high-powered computer is also required, to do this successfully. Conversely, Ripple is a centralised asset, which can't be mined. A fixed number of tokens were created by the organisation and this limit will never be added to.