You might think you have a web server all to yourself because you are leasing space from a web host, but don’t be fooled. If you have a cheap web hosting plan, then you likely do not have a dedicated server. You are using a shared server and that means other people have their websites and data hosted on the same server.
A dedicated server is one that you have all to yourself. You have no neighbors doing sketchy things on your server, inviting viruses, worms, and other nasties. It may or may not be an element of cloud computing.
If your dedicated server is one that you own and is situated at a data center facility remotely from your location, then it’s a part of a colocation service.
Another version of the colocation service is the managed server. You own it, but it’s managed by someone else. Often, this type of service is pre-arranged in that the manager sells you the server and continues to manage it for you.
If the dedicated server is loaded with software and applications that otherwise would not be included in a hosting plan, then that dedicated server also exists in a cloud computing environment. It likely costs more than a typical dedicated server, but when it comes to cloud computing, you get what you pay for. That’s not necessarily a bad thing.