Suppose two persons that have data stored on some media, say hard drives. If the two persons need to share this data with each other, what will they do?
This question is the basis on which the networking principle is built. The two persons can send the data to each other by copying it to movable drive say flash memory and giving it to each other. This can be well if it will not be happening continuously. But what if the two persons need to send data every day or even every hour? It will be difficult to send it to each other especially if they remote from each other.
The idea of networking has been arisen from such cases. Instead of sending data between two or more people on movable devices such as floppy disks, they can easily connect their computers to each other. Every person who wants to transfer the data to his friend can easily transfer it through the network.
So how will the data be transferred across the network? Simply by connecting computers of different persons to each other by means of cables the data can be easily transmitted. Thus the media will be cables rather than movable devices although it can be also wireless device. The wireless device will send the data in air by electromagnetic waves. It will be electrical pulses if the data are transmitted on cables.
In fact networks can be used not only to share data but also to share devices such as printers and CD-ROM. One user on a floor can use a printer that is connected to another computer on anther floor by means of the network. The same is true for CD-ROM. This must be configured on both computers by the operating system. This benefit of networking makes it helpful for people to use remote devices on their office. Also it reduced the cost because on printer or one CD-ROM is used for all members of the network.
Mainly the network will be composed of a set of computers and a printer. This set of computers will be responsible for sending the data to each other. One computer also may use the printer to print documents. If the network looked like this, it will be called peer to peer. In this scheme, all computers are the same and have equal processing power. The information is also distributed across them equally. There is no device that has more data in its hard drive.
On the other hand, if there is at least one computer in the network that has more stored data and more processing power and speed, then the scheme will be called server-based networking. The computer that has the more data storage and the higher processing power will be called the server. This scheme can be defined also as a client-server based model because the other computers in the network that have normal processing power will b treated as clients that will request data from the server. The internet is build over this scheme where the home computers are the clients and the computers that serve them are called servers. The most popular server type is the web server which forwards page to the clients in the home or offices.