Centralised crypto is a digital resource designed to be used as a medium of trade. crypto-coins are added by mining. Any person is able to participate if they have a a device. Mining uses a large amount of hours and electricity, though. A high-powered machine is also needed, to do this effectively. Conversely, Ripple is a centralised asset, which is unmineable. A fixed number of tokens were created by the company and this number will not be added to.