Plug-in or add-on or extension are basically programs that you can easily install and bring into use as part of your web browser. Well, the use of installing plug-ins are huge for instance, a plug-in enables third-party developers to create merits which make the use of an application even broader. Following are a few more key usage of plug-ins:
Support for New Features:
Providing support to the easy addition of new features is one of the vital tasks of a plug-in. They instantly configure data and quickly make your application adaptable to allow new features work accurately. Once a plug—in is installed, you are all set to use the wide range of features, benefits, etc. and that too without troubling yourself much.
Reduce the Size of an Application:
A plug-in helps to reduce the size of an application to a large extent and thus, you can utilize the leftover space more efficiently. Moreover, you can install some more programs or keep your website even lighter with the use of a few smart plugins like Regenerate Thumbnails, AJAX Thumbnail Rebuilt, etc. available on various platforms.
Have the Source Code Categorized:
Plug-in helps you get source code separated from an application because of the many incompatible software licenses. This not only allows users get their tasks done instantly, effectively and with a huge convenience, but improves security as well.
Plug-ins is a software component that is known to add specific features to an existing program. Most often, they are usually an add-on to a web browser to give it an additional functionality. They offer additional features to the program. 
Macromedia Flash Player:
The best example for a plug-in would be that of the Macromedia Flash Player, which allows the web browser to display animations and videos using the Adobe Flash format. Plug-ins of different types have different functions. This can be best explained by taking the help of certain examples:
- Macromedia Flash Play – As already stated, this plug-in enable the user to play videos and animations that are in the Flash format.
- Java – Content on the Web that makes use of the Java requires that you employ this plug-in to use and view such content.
- QuickTime – This plug-in is also used to play audio and video.
- Silverlight – The Microsoft Silverlight plug-in is meant for playing audio and video too.
- Adobe Acrobat – This plug-in help in viewing PDF files on the Web.
- Security plug-ins – The antivirus installed on your PC might also offer a plug-in that protects you when you are surfing the Internet via your Web browser.
These are just a few of the most popular plug-ins that almost all users generally use. Plug-ins are a good way to increase the functionality of any existing program but make sure you download them from a trusted source for security reasons.
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