Has a meaning that can vary with context. The most common meaning in WWW browsers is reader (runtime, playback, view) software that will "plug" into the browser such that when a file extension (e.g., PDF, TBK, WAV, AVI, MOV, etc.) is encountered the browser will view or download the file automatically and run that file. Most plug-in readers are free. Examples include the PDF Acrobat reader from <http://www.adobe.com/>, the shockwave reader from < http://www.macromedia.com />, the neuron reader from <http://www.asymetrix.com/>, and movie readers from <http://www.texas.net>. VRML readers are usually browser plug-ins. A summary of browser plug-ins is contained in "Get Plugged In: Navigator Plug-Ins That Liven Up the Web," PC Magazine, May 28, 1996, pp. 44-60. (See also MIME , Internet , Browser , and World Wide Web )
PLUG-IN
Meaning of PLUG-IN in English
Jensen's Technology English Glossary. Английский словарь фирмы Jensen Technologies. 2012