A Server is a machine or computer program that provides data or functionality for other machines or programs. We call the other devices or programs ‘clients.’ Most commonly, the term refers to a computer that provides data to other computers. The data may be served to systems on a wide area network (WAN) over the Internet. Alternatively, it may serve the data to LAN systems. LAN stands for local area network.
Provide shared resources
Servers are the lifeblood of any network. They provide the shared resources that the network users need, such as e-mail, Web services, databases, file storage, etc.

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