A system on a network that provides a service to other systems connected to the network. The term was originally restricted to the case where both the server and the systems it served were on the same local area network, and where the server was likely to be expensive in comparison with the systems it served. The term is now used much more generally, applying to systems where the server and the system to which it provides a service (the client) may be linked by a metropolitan area network or wide area network, and where the server may be much less costly than the client. See also client/server, compute server, file server.