Understanding computer networks

A computer network is composed of multiple connected computers that communicate over a wired or wireless medium to share data and other resources. For instance, a home computer network may consist of two or more computers that share files and a printer using the network. The size and scalability of any computer network are determined both by the physical medium of communication and by the software controlling the communication.

We can broadly classified the computer networks into three main categories. They are

Local Area Network (LAN)
Metropolitan Area Network (MAN) &
Wide Area Network (WAN)

Local Area Network (LAN)
A network covering a small geographic area, like a home, office, or building is known as LAN. Current LANs are most likely to be based on Ethernet technology. The hub is just like what it sounds. A bicycle wheel uses a hub and spokes - all the spokes connect to a central point - the hub.
LANs use different technologies to link computers together. Depending on the circumstance, the computers in the network might be connected using cables and hubs. Other networks might be connected strictly wirelessly. It depends on the number of PCs that you are trying to connect, the physical layout of your workspace, and the various needs that you have as you develop your network.
The defining characteristics of LANs, in contrast to WANs (wide area networks), include their much higher data transfer rates, smaller geographic range, and lack of a need for leased telecommunication lines. Current LAN technologies generally operate at speeds up to 10 Gbit/s. This is the data transfer rate.

Metropolitan Area Network (MAN)
A Metropolitan Area Network is a network that connects two or more Local Area Networks together but does not extend beyond the boundaries of the immediate town, city, or metropolitan area. Multiple routers, switches & hubs are connected to create a MAN.

Wide Area Network (WAN)
A WAN is a data communications network that covers a relatively broad geographic area (i.e. one country to another and one continent to another continent) and that often uses transmission facilities provided by common carriers, such as telephone companies. The highest data rate commercially available, as a single bitstream, on WANs is 40 Gbit/s, principally used between large service providers.