A server in computing is:
- A computer software application that carries out some task on behalf of users. This is usually divided into file serving, allowing users to store and access files on a common computer; and application serving, where the software runs a computer program to carry out some task for the users. This is the original meaning of the term.
- The term is now also used to mean the actual computer on which the software runs. Originally server software would be located on a mainframe computer or minicomputer. These have largely been replaced by computers buit using a more robust version of the microprocessor technology that is used in personal computers, and the server term was adopted to describe such microprocessor based machines.
A Server computer shares its resources, such as peripherals and file storage with the users' computers, called clients, on a network. It is possible for a computer to be a client and a server simultaneously, by connecting to itself in the same way a separate computer would.
Many large enterprises employ numerous servers to support their needs. A collection of servers in one location is often referred to as a server farm.
Server Operating Systems
The rise of the microprocessor based server was facilitated by the development of several versions of Unix to run on the Intel microprocessor architecture, including Solaris, Linux and FreeBSD. The Microsoft Windows series of operating systems also now includes server versions that support multitasking and other features required for servers, beginning with Windows NT.
Mainframes and minicomputers were originally accessed using dumb terminals, which were unable to carry out any significant processing. This largely ended with the widespread use of personal computers by users.