A cloud hosting service means that every single part of your web presence will be handled by an independent server. For instance, your files and databases will be managed by different machines and since just one kind of processes will run on a server, every machine will perform better and will use its resources to the highest. Whether you will get a genuine cloud service or not also depends on the CP that you'll use to manage your account. Since most control panels were made to operate on a single server, they are unable to work on a cloud platform regardless of what a given web hosting provider may advertise. In the event that one service stops responding, the whole server can go down, so your websites will not be accessible. This is the reason why you should check what service you'll actually receive in case you are looking for cloud internet hosting before you buy anything.