A network is any collection of independent computers that are interconnected for the purpose to exchange information over a shared communication medium. There are several types of networks all having the same basic function, but are classified by the geographical area they support. Which are listed as: LAN, WLAN, MAN, WAN, and GAN, these will be discussed later in the unit.

For this course, the focus is on Local Area Networks (LAN), it is a specialized network that is typically confined to a limited geographic area, as a single building, campus, or other geographically limited area. A LAN may be as small as two computers or as many as thousands of linked computers. A major factor with the proliferation of LANs was standard networking protocols.

Fig. Types of Networks Source: http://2.bp.blogspot.com