What is a server?

A server is a computer system who's primary purpose (or even sole purpose) is to host files and/or applications and provide access to them on a network.
Server can share resources with various clients. 

Servers are often depended upon to provide services which are crucial to an organization. Therefore server-specific hardware is available which is engineered to be as robust as possible. 

It is not always necessary to build a server with this level of reliability, and so some servers are built using desktop parts. These machines can still be referred to as a server as the term refers to the systems primary purpose rather than its construction.
The counterpart to a server is a "client." Any computer which is accessing the server is said to be that servers client. Many servers are designed to handle very large numbers of clients, these servers must be very powerful and must have a very fast connection to their network in order to be able to do this reliably. 

The word "server" can also refer to a specific application, one which "serves" data or services to other applications. In this case, it is possible for the server and the client to both reside on the same system.

A server is any combination of hardware or software designed to provide services to clients. When used alone, the term typically refers to a computer which may be running a server operating system, but is commonly used to refer to any software or dedicated hardware capable of providing services. Another way of saying it: a server in a network is a central computer that is accessed by other networked computers which are operated by individual users. A server is maintained by a network technician, but in general it functions on its own without a human operator. 

A server is a host, it is used to host a network over a WAN, LAN, and any other connection types. with a network you can transmit files between computers and onto a system stored within the server. It is used to help computers to communicate with minimal collisions on the network route. A server is a computer with more storage space to hold all of the files that are used on each of the computers i.e. each computer that is used will back up the information or transmit it to the server to be stored securely and or backed up at the end of a period of time.

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