What is Computer Network ?

Computer network can be interpreted as a series of two or more computers. These computers will be connected to each other by a communication system. With computer networks is possible for every computer that netted in it can be exchanged data, programs, and other computer resources such as storage media, printers, and others. Computer network that connects computers located at different locations can also be used to send electronic mail (e-mail), send data files (upload) and retrieve data files from other places (download), and various activities access to information on the location separately.
The main purpose of a computer network is resource sharing (read: the resources), in which a computer can utilize the resources of other computers that are in the same network.

The development of data communications technology and computer networks today are no longer limited only to the computer. Various communication technology devices that are present today evolved following the development of computer technology, many of which integrate computer devices such as microprocessors, memory, display, storage, and communications technologies into it but once the technology is developed for computers that we can find are now used on the go computer network technology.
A computer network consists of:
minimum of two computers network card (network interface card / NIC) on each computer medium connection, which connects a network card one computer to another, commonly referred to as a data transmission medium, may be a wired or wireless or non-wired (wireless such as radio, microwave, satellite, etc.).
    network operating system software (network operating system software / Noss) which serves to make the management of network systems, for example: Microsoft Windows 2000 Server, Microsoft Windows NT, Novell Netware, Linux, and so on.
    interconnect devices such as Hub, Bridge, Switch, Router, Gateway, when the network was formed more far-reaching.