In order to tell you what the difference between virtual and dedicated servers is we should explain the meaning of “virtual server” and “dedicated server” first.
Dedicated server is a physical machine that belongs to one client. It means that if you want to buy a dedicated server, all the machine’s resources will belong to you exclusively. Only you will be able to use the capacity of this machine. You will be able to do whatever you want on this server, even launch virtualization technologies on your dedicated server or create several virtual servers (VPS)
Also very widely known as VPS (Virtual Private Server) or VDS (Virtual Dedicated Server), which is pretty much the same. A software environment that allows you to launch several isolated servers with the help of virtualization technologies (we use KVM) can be created on a dedicated server.
A user that logs in to such server will have full access to it as if he worked with a physical server. However, in this case, all the resources of the physical machine will be divided between all the virtual environments (clients).
However, it doesn’t mean that a virtual server is necessarily worse than dedicated. It highly depends on the configuration parameters. Sometimes, a virtual server’s configuration can outperform configuration of a dedicated server. That’s why when you buy a virtual server, you should pay close attention to the configuration that you need. Flexible plan is always better, because you can always change your configuration on the go.
One of the disadvantages of a virtual server is dependence on other clients of the node (who use the same physical server where your virtual server is hosted). If any of the clients begin to experience excessive load, it may affect performance of virtual servers of other clients.