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Related to plug-in: Java plug-in


(computer science)
A small software application that extends the capabilities (such as multimedia, audio, or video) of a browser.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.


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 which display or interpret a particular file format or protocol such as Shockwave, RealAudio, Adobe Systems, Inc. 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, can usually be downloaded for free and are stored locally. Plug-ins come in different versions specific to particular operating systems (Microsoft Windows 3.1, 3.2, and Macintosh are available).

Compare applet.

Plug-in Plaza.

PC Mag Plug-ins.
This article is provided by FOLDOC - Free Online Dictionary of Computing (


Software that is installed into an existing application in order to enhance its capability. For example, plug-ins are widely used in image editing programs such as Photoshop to add some special effect. Plug-ins are added to Web browsers to enable them to support different types of content (audio, video, etc.). The term is widely used for software, but can also refer to a plug-in module for hardware.

Plug-In, Add-On, Extension
Although the terms "plug-in," "add-on" and "extension" are used synonymously, a plug-in implies adding new functionality, whereas add-on and extension imply more of a modification to an existing function. These distinctions are not evident in the literature however. See plug-in free and browser plug-in.
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References in periodicals archive ?
The proprietary-format data file from the controller is converted by a manufacturer-specific plug-in into an instance of the object model.
"Now, they can purchase identical GuardShield 450L sticks and customise the features with different plug-ins," he added.
The second type, known as a parallel or blended plug-in hybrid, uses an electric motor in conjunction with a gasoline engine, the former powering the car in restrained driving conditions while the second kicks in when you demand more power from the car or when the battery is depleted.
Plug-ins have served us well, but with recent advances in technology and browser capabilities, there are more efficient and secure ways to deliver existing and new features without the use of plug-ins.
They predict that the electrified vehicle market will overcome its current challenges, writing, "Plug-ins face higher hurdles than hybrids did a decade ago, so a steady increase in sales and number of models should be seen as a positive sign that plug-ins are poised to be a significant segment in the U.S.
The association has consistently campaigned for plug-in grant users to be offered longer-term incentives, including parking concessions and financial help when installing plug-in points.
The new Honda Accord Plug-ins are situated at 10 locations throughout Manhattan, with Zipcar branded parking spots and charging stations at each site.
People also often end up installing unwanted plug-ins when installing applications or updates (free anti-virus applications are among the usual suspects) by failing to 'un-tick' the appropriate option.
Plug-ins have traditionally been created to offer various functionality to websites to enhance the end-user experience, says Hanegan.
Apple(R), Cupertino, Calif., has unveiled Aperture(TM) 2.1, which has introduced an open plug-in architecture that makes it easy for photographers to use specialized third party imaging software right from within Aperture.
One thing that will enable them the most is the deployment of plug-in cars, because they provide a way to store this renewable energy.
Integrify ( has released Plug-In Central for its Integrify 4.0 software.