Local-area networks are networks that span a relatively small space. Usually, LANs only occupy one building, but they can also span multiple buildings if the buildings are in close proximity- within a few kilometers of each other. Within one local-area network, many computers can be connected. This is often used in businesses because it lets multiple users share files as well as expensive devices like laser printers.

The computers and other devices on a local-area network can be connected in different ways. For example, they could be connected using wires such as coaxial cables, copper wires, or optical fiber. There is even a type of LAN that is wireless!

Wireless LANs:

Wireless networks made a major breakthrough in the late 1990s. Wireless LANs, just like regular LANs, can transport information to different computers throughout a whole building, a few buildings, or even a whole city! Wireless LANs make networking easy because there are no wires to get in your way!

So, how can we transport data and information without any wires? Well, wireless LANs use one of two types of electromagnet airwave-infrared (IrDA) or radio frequency (RF).

There are two modes of wireless LANs: Ad Hoc LANs and Infrastructured LANs.

Ad Hoc LANs: With Ad Hoc LANs, mobile devices, like laptops or handheld computers, can get together and establish peer-to-peer communications. They can transfer data between themselves as they wish; there is no access point and no connection to any sort of wired network. You can easily set up a wireless network anywhere!

Infrastructured Wireless LANs: The major difference between infrastructured mode and ad hoc mode is that in infrastructured LANs, the wireless network is connected to separate wired network.

LANs can be connected to other LANs, or even to wide-area networks, or WANs. This is done by using components like bridges and routers.

You might remember from the article about what networks are that all networks have a set of rules, called protocols, that they use while transferring data. These rules ensure that the data and information do not collide with each other while they are being transferred. Computers on most local-area networks use one of two major protocols:

1. Ethernet
2. Token Ring