applet: A small program often used to add features to a web page. When activated by a browser, it is downloaded to the viewer's computer and run from there.

ARPAnet (Advanced Research Projects Agency network), later DARPA (Defense Advanced Research Projects Agency): Government agency that funded the development of the network that later became the Internet.

bandwidth: The amount of information that can be distributed in a given time. If one thinks of "pumping" data like water, bandwidth is the width of the pipe.

browser (or web browser): A software program used to view pages on the World Wide Web and to navigate using hypertext links.

CD (compact disc): A shiny disc, written on and read by laser, that can hold a large amount of data, such as text, sound recordings, and graphics images.

chat program: Software that allows on-line users to carry on a conversation by typing...