Ok so I have a question.

There is a type of networking where you have 1 server local or remote. Then you have the client machines, but they are just boxes basically. They only log into the server and everything runs off of that server. Of course there are multiple user accounts, but can any one tell me what type of network this is called.

Also there was at one time a virtual provided of this. They hosted your server and set up your clients but i cannot remember what they were called.

So what is this type of network called
Who offers this virtual service?

Thanks