Add-on

An add-on is a software extension that adds extra features to a program. It may extend certain functions within the program, add new items to the program's interface, or give the program additional capabilities. For example, Mozilla Firefox, a popular Web browser, supports add-ons such as the Google toolbar, ad blockers, and Web developer tools. Some computer games support add-ons that provide extra maps, new characters, or game-editing capabilities.

Most add-ons are available as self-installing packages. This means the user can simply double-click the add-on package to install the files for the corresponding program. Other add-ons may require the user to manually move files into specific directories. While not all programs support add-ons, many programs are now developed with add-on support, since it provides a simple way for other developers to extend the functions of the program.

However, not all software programs refer to these extra features as "add-ons." For example, Dreamweaver supports "extensions," which add extra Web development features, while Excel can import "Add-Ins" that provide the user with extra spreadsheet tools. Many programs also support plug-ins, which may be considered a type of add-on.

Updated December 22, 2008 by Per C.

quizTest Your Knowledge

What is a pop-up window with a warning called?

A
Interstitial
0%
B
iFrame
0%
C
Beacon
0%
D
Alert box
0%
Correct! Incorrect!     View the Alert Box definition.
More Quizzes →

The Tech Terms Computer Dictionary

The definition of Add-on on this page is an original definition written by the TechTerms.com team. If you would like to reference this page or cite this definition, please use the green citation links above.

The goal of TechTerms.com is to explain computer terminology in a way that is easy to understand. We strive for simplicity and accuracy with every definition we publish. If you have feedback about this definition or would like to suggest a new technical term, please contact us.

Sign up for the free TechTerms Newsletter

How often would you like to receive an email?

You can unsubscribe or change your frequency setting at any time using the links available in each email.

Questions? Please contact us.