Computers that are connected with one another; the system is called computer network. Creating these networks is motivated for various reasons. Firstly the possibility is open for mutual usage of different devices. One computer can use the hard drive, or printer of another computer of the network, it is possible to work with them the way as it would be the part of the first computer. Itís called sharing of hardware resources. Itís also possible use programs, files mutually, sharing software resources.
In these days it is getting to be more and more important to use the network as a communication channel. Using electronic mails one can send and receive letters very quickly and cheap regardless of the distance. Other networks provide services for verbal communication.