In most common use, server is a physical computer dedicated to running one or more such services (as a host), to serve the needs of users of the other computers on the network. Depending on the computing service that it offers it could be a database server, file server, mail server, print server, web server, gaming server, or some other kind of server.
In the context of Internet Protocol (IP) networking, a server is a program that operates as a socket listener.
Servers often provide essential services across a network, either to private users inside a large organization or to public users via the Internet.