Ans :
We use a Computer Network for the following reasons:
a) Resource sharing: A network is needed because of the desire to share the sharable programs, data, and equipment available to anyone on the network without regard to the physical location of the resource and the user. You can also
share processing load on various networked resources.
b) High reliability: A network may have alternative sources of supply (e.g., replicated files, multiple CPUs, etc.). In case of one resource failure, the others could be used and the system continues to operate at reduced performance. This is
a very important property for military, banking, air traffic control, and many other applications.
c) Cost-benefit advantage: A network may consist of many powerful small computers, one per user. You can keep the data and applications on one or more shared and powerful file server machines. This is called the client-server model.
Such model offers a much better price/performance ratio than old mainframes. At present many server services have been moved to Internet based resources set up by a third party and shared by many (called cloud). This allows users to use powerful server applications and data services without maintaining servers. Such system may bring down the cost further. However, such models still have several issues that are being debated.
d) Scalability: The ability to increase system performance gradually by adding more processors (incremental upgrade).
e) Powerful communication medium: Networks make cooperation among far-flung groups of people easy where it previously had been impossible.
In the long run, the use of networks to enhance human-to-human communication may prove more important than technical goals such as improved reliability.
One of the most popular application of network is the World Wide Web which is an application of Internet. Let us introduce you to internet in the next subsection.
