If computers are connected to the network in close proximity to one another, as in the same building or group of buildings, the network is called a local area network (LAN). If the computers are connected over a large metropolitan area it is called a metropolitan area network (MAN). If the network extends over a large geographic area, it is called a wide area network (WAN). WANs are typically connected using long-range telecommunication links and may connect other LANs or MANs together.

LANs are increasingly being divided into workgroups connected via common backbones to form VLANs (virtual LAN). Because VLANs are based on logical instead of physical connections, they are extremely flexible. VLAN provide solutions to improve inherent LAN performance problems. VLAN technology is cost effective and it's an efficient way to segment a LAN.

New upcoming technology is Wireless local area network (WLAN). Wireless technology has dramatically increased mobility and productivity in the work place by providing users with flexible tools that are both efficient and effective, also allows users to constantly be connected to the network, no matter where they are.

Virtual private networks (VPN) offers an inexpensive secured and encrypted method for connecting business partners, branch offices and remote employees to central offices and to each other and share information and resources across an organization locally, regionally or globally and enabling ideas to be exchanged between people all over the world via the Internet.