In regards to Internet hosting, cloud architecture refers to using a separate server for each aspect of the Internet hosting service. Such a setup results in significantly better performance since one machine will be used just for file storage, another only for running databases, and so on, thus different system processes will not run on the exact same machine. This will decrease the probability of system errors considerably and will allow your Internet sites to operate faster, not mentioning the better uptime. If you're looking for this kind of service, you should double check that you will really receive it since a lot of companies advertise cloud web hosting plans, but the control panels they use aren't designed to work in a real cloud and can function only on a single server. The trouble with using a single machine is that in the event that one service crashes or generates high load, the whole server will most likely go offline, so your Internet sites will no longer be accessible.