Virtual private server (VPS) is a term used by Internet hosting services to refer to a virtual machine. The term is used for emphasizing that the virtual machine, although running in software on the same physical computer as other customers’ virtual machines, is in many respects functionally equivalent to a separate physical computer, is dedicated to the individual customer’s needs, has the privacy of a separate physical computer, and can be configured to run server software.
The terms virtual root server (VRS) and virtual dedicated server (VDS) are also used as synonyms of VPS. However, the latter also occasionally indicates that the server does not use burst/shared RAM through multiple machines and may use individual CPU cores. The term Cloud Server is a close concept and designates a virtual private server, where resources allocated are guaranteed, it can usually be reconfigured anytime (upgrade or downgrade) and are paid per usage (not prepaid).