<tool> A file containing data used to alter, enhance, or extend the operation of a parent application program. One of the first uses of this term was in Silicon Beach's SuperPaint application (late 1980s?) for the Macintosh. It had a Plug-ins folder containing different tools and effects.
The Netscape Navigator World-Wide Web browser supports plug-ins. A plug-in is specific to a particular operating system (Microsoft Windows 3.1, 3.2, and Macintosh are available) and displays or interprets a particular file format such as Shockwave, RealAudio, Adobe PDF, Corel CMX (vector graphics). The file to be displayed is included in a web page using an <EMBED ...> HTML tag. Plug-ins, both commercially and indepently authored, are usually downloaded for free and stored locally.
Compare applet.
(25 May 1996)