From Wikipedia (HERE) (because they do it best):
A virtual private server (VPS) is a virtual machine sold as a service by an Internet hosting service.
A VPS runs its own copy of an operating system (OS), and customers may have superuser-level access to that operating system instance, so they can install almost any software that runs on that OS. For many purposes they are functionally equivalent to a dedicated physical server, and being software-defined, are able to be much more easily created and configured. They are priced much lower than an equivalent physical server. However, as they share the underlying physical hardware with other VPSs, performance may be lower, depending on the workload of any other executing virtual machines.
Westlinks Online provisions VPS hosts exclusively (as opposed to dedicated or shared hosts) because VPSs make the most sense for our product offerings. If for some reason you would like to have your services hosted on a dedicated server, we could do that for you at an additional cost. Please ask!