Introduction to Computer Networks
A computer network is a collection of computers and other devices that are connected together in some way to enable communication to take place between them. There are many different kinds of computer network in existence, ranging in size from the personal area networks (PANs) used to connect the computing resources used by a single individual, to large-scale and complex internetworks (networks of interconnected networks) that span the entire globe. Networks facilitate many forms of electronic communication, allow information to be shared by a large and distributed user community, and provide access to an ever more diverse range of services. The exponential growth in the demand for networking products and services means that network technology will continue to evolve at a breathtaking pace.