Bandwidth is defined as the amount of information that can flow through a network connection in a given period of time.
Bandwidth is not free.
It is possible to buy equipment for a local-area network ([[LAN]]) that will provide nearly unlimited bandwidth over a long period of time. For wide area network ([[WAN]]) connections, it is almost always necessary to buy bandwidth from a service provider. In either case, an understanding of bandwidth and changes in demand for bandwidth over a given time can save an individual or a business a significant amount of money. A network manager needs to make the right decisions about the kinds of equipment and services to buy.
Bandwidth is a key factor in analyzing network performance, designing new networks, and understanding the Internet.
The delivery over the network of rich media content, including streaming video and audio, requires tremendous amounts of bandwidth. IP telephony systems are now commonly installed in place of traditional voice systems, which further adds to the need for bandwidth.