Computer networks are typically used to perform thousands of functions through the sharing of data. These networks have become an integral part of the business world, helping companies exchange information and work together more effectively. This information is usually processed in a way that ensures that no information is lost or corrupted, which makes the network one of the most important pieces of technology used by many businesses.

A computer network may consist of a single router, a collection of routers, or a collection of network nodes. The nodes are what link the personal computers and devices on the network. The network has physical access only from the nodes, while the computers on the network can access the network nodes either by utilizing their built-in IP addresses or by requesting IP addresses via the internet. There may also be a central administrator for the network. In a wide-area network, the administrator does not necessarily need to be located in the same area as the computers on the network.

Microsoft Windows operating systems use the Windows Networking Model. Apple Macintosh computers use the SMTP networking model, which is heavily based off of the Windows Networking Model. Unix-like operating systems like Linux and BSD use the Unix Networking Model. The Internet itself has its own networking model called the Internetwork Model, which is used in home networks, Internet cafes, corporate networks, and other places where computer networking is needed.

A Wide Area Network, or WAN, is a type of computer network that covers a large area. Unlike a Local Area Network, which is used for localized purposes like dial up connections, Wide Area Networks can span between countries or continents. A Wide Area Network is usually broken into components called nodes. A router links the various nodes together, while a switch connects the nodes to each other. Based on the technology that a Wide Area Network uses, a Wide Area Network has different security requirements than a Local Area Network.

Intranets have been around for some time now, but they are relatively new when it comes to computer networking. Before they were developed, people would write letters and memos by hand instead of typing them on a computer keyboard. They are also useful for allowing people to share information and work together, regardless of geographical boundaries. Intranets run on a different technology than the Wide Area Network, called the Information Highway. Intranets were built to provide a way for people to work together in an online environment and are very similar to the Internet, with email being the most common method of communication.

Telephone lines are another part of the Network that is less understood than it should be. Just because you see two phone lines connected to a given computer does not mean that they are connected. In fact, when you call one line, your message is sent to three or more computers, depending on how many telephone lines are available. Because telephone lines are used as a medium of communication in so many other areas of the world, it is important to understand how they got their start and how they work in our day-to-day lives