Computer Netwoking

A computer network is multiple computers connected together using a telecommunication system for the purpose of communicating and sharing resources.

Experts in the field of networking debate whether two computers that are connected together using some form of communications medium constitute a network. Therefore, some works state that a network requires three connected computers. For example, "Telecommunications:

Glossary of Telecommunication Terms" states that a computer network is "A network of data processing nodes that are interconnected for the purpose of data communication", the term "network" being defined in the same document as "An interconnection of three or more communicating entities". A computer connected to a non-computing device (e.g., networked to a printer via an Ethernet link) may also represent a computer network, although this article does not address this configuration.This article uses the definition which requires two or more computers to be connected together to form a network.]
The same basic functions are generally present in this case as with larger numbers of connected computers.

This article or section does not adequately cite its references or sources.

Basic and Essential components of computer network

Computers
Many of the components of an average network are individual computers, which are generally either workstations (including personal computers) or servers

Types of workstations

There are many types of workstations that may be incorporated into a particular network, some of which have high-end displays, multiple CPUs, large amounts of RAM large amounts of hard drive storage space, or other enhancements required for special data processing tasks, graphics, or other resource intensive applications. (See also diskless workstation).

Types of servers

The following lists some common types of servers and their purpose.

File server
Stores various types of files and distributes them to other clients on the network.

Print server
Controls and manages one or more printers and accepts print jobs from other network clients, spooling the print jobs, and performing most or all of the other functions that a workstation would perform to accomplish a printing task if the printer were connected directly to the workstation's printer port.

Mail server
Stores, sends, receive, routes, and perform other email related operations for other clients on the network.

Fax server
Stores, sends, receives, routes, and performs other functions necessary for the proper transmission, reception, and distribution of faxes.

Telephony server
Performs telephony related functions such as answering calls automatically, performing the functions of an interactive voice response system, storing and serving voice mail, routing calls between the Public Switched Telephone Network (PSTN) and the network or the Internet (e.g., voice over IP (VoIP) gateway), etc.

Proxy server
Performs some type of function on behalf of other clients on the network to increase the performance of certain operations (e.g., perfecting and caching documents or other data that are requested very frequently) or as a security precaution to isolate network clients from external threats.

Remote Access Server (RAS)
Monitors modem lines or other network communications channels for requests to connect to the network from a remote location, answers the incoming telephone call or acknowledges the network request, and performs the necessary security checks and other procedures necessary to log a user onto the network.

Application server
Performs the data processing or business logic portion of a client application, accepting instructions for operations to perform from a workstation and serving the results back to the workstation, while the workstation performs the user interface or GUI portion of the processing (i.e., the presentation logic) that is required for the application to work properly.
Web server
Stores HTML documents, images, text files, scripts, and other Web related data (collectively known as content), and distributes this content to other clients on the network on request.

Backup server
Has network backup software installed and has large amounts of hard drive storage or other forms of storage (tape, etc.) available to it to be used for the purpose of ensuring that data loss does not occur in the network.'''

Game server
Dedicated computer system running game hosting software. Most run 24/7.