Server
1. A program which provides some service to other (
client) programs.
The connection between client and server is normally by means of
message passing, often over a
network, and uses some
protocol to encode the client's requests and the server's responses.
The server may run continuously (as a
daemon), waiting for requests to arrive or it may be invoked by some higher level daemon which controls a number of specific servers (
inetd on
Unix).
There are many servers associated with the
Internet, such as those for
HTTP,
Network File System,
Network Information Service (NIS),
Domain Name System (DNS),
FTP,
news,
finger,
Network Time Protocol.
On Unix, a long list can be found in /etc/services or in the
NIS database "services". See
client-server.
2. A computer which provides some service for other computers connected to it via a network.
The most common example is a
file server which has a local disk and services requests from remote clients to read and write files on that disk, often using
Sun's
Network File System (NFS)
protocol or
Novell Netware on
PCs.
Another common example is a
web server.
[
Jargon File]
