The primary factor that determines whether or not Web-based tutorials can incorporate audio, video, and animations is the amount of "bandwidth" that is available. Bandwidth, in simple terms, is the speed of the student's connection to the Internet or Intranet. The more bandwidth, the faster the connection will be, which is needed for downloading or "streaming" large media files such as audio and video. Often, bandwidth is referred to simply as high bandwidth, which means capable of delivering multimedia; or low bandwidth, which can handle text and graphics only.

Bandwidth is measured in bits per second (bps), which means how many pieces of data can be transmitted every second during the connection. It is usually measured in increments of thousands (Kbps) or millions (Mbps).

As a rule of thumb, students who are dispersed geographically and accessing the Web using a dial-up modem (i.e., they must use a standard telephone line to gain Internet access) are considered to have a low bandwidth connection. With current technologies, it is not practical to use audio or video extensively in training programs because of the long delays downloading the files, and the associated technical glitches. Even the latest video compression technologies only display video in postage-stamp size screens using half the normal frame rate.

Students who work in a traditional office environment, in the same building or location as the Intranet server, are likely to have a high bandwidth connection. This is because employees are usually connected to the Local Area Network (LAN) using a technology called Ethernet, or 10baseT. The figure below shows that this connection is almost 100 times faster than traditional dial-up modems. This type of connectivity enables audio and video delivery with generally the same speed and quality as a CD-ROM.

Though still uncommon, cable modems are becoming an increasingly popular way to connect to the Internet from home in the United States. These modems connect to a standard cable-TV line and provide extremely fast -- high bandwidth -- access to the Internet. Less popular but also available in many areas in the United States are DSL lines, which are offered by the phone companies. DSL lines are also considered to be high bandwidth connections.