In today's world, a computer network is much more than a collection of interconnected
devices. The computer network is the resource, which enables to analyse, organise, and
disseminate the information that is essential to profitability. The rise of intranets and
extranets is the important aspect of computer networking. Intranets and extranets are
private business networks that are based on Internet technology. The businesses are
currently implementing intranets at a breakneck pace and for one reason only—an intranet
enables a business to collect, manage, and disseminate information more quickly and
easily than ever before. Many businesses are implementing intranets simply to remain
competitive; businesses that delay are likely to see their competition outdistance them. In
this article we are presenting the basic definition of computer network, characteristics of
transmission media-bounded and unbounded, networking components and a brief review
of the applications of networking in IT enabled services