(2) A virtual machine environment from Microsoft for Windows servers. See Microsoft Virtual Server.
(3) Multiple servers that appear as one system image to the operating system or to the network administrator. See network virtualization.
(4) One instance of a Web or application server running in a single computer that is hosting multiple Web or application servers. See Web hosting.
(5) Multiple servers that appear as one server for load balancing. For example, all clients use the IP address of the virtual server, which uses address translation to point to a real server based on its load balancing algorithm.