The term extension in a computing context most commonly refers to a computer program that although not useful or functional in its own right, is designed to be incorporated into another piece of software in order to enhance, or extend, the functionality. A filename extension is a suffix to the name of a computer file applied to show its format. ... A computer program is a collection of instructions that describe a task, or set of tasks, to be carried out by a computer. ... Computer software (or simply software) refers to one or more computer programs and data held in the storage of a computer for some purpose. ...

Examples of software applications that support extensions include the Mozilla Firefox Web browser, Adobe Photoshop and Microsoft Windows Explorer shell extensions. It is common to find that applications whose scope is potentially unbounded will feature an extensions interface (API), and the API description will often be published so that third-party developers can produce extensions. Mozilla was the official, public, original name of Mozilla Application Suite by the Mozilla Foundation, nowadays called SeaMonkey suite. ... Firefox may refer to: Firefox (novel), written by Craig Thomas, published in 1978 Firefox (film), the 1982 movie starring Clint Eastwood, based on the novel Firefox (arcade game), the laserdisc arcade game based on the movie Mozilla Firefox, a web browser The Red Fox or the Red Panda, based on... An example of a web browser (Internet Explorer), displaying the English Wikipedia main page. ... Renewal of the surface coating of an adobe wall in Chamisal, New Mexico Adobe is a natural building material composed of sand, sandy clay and straw or other organic materials, which is shaped into bricks using wooden frames and dried in the sun. ... Adobe Photoshop is a bitmap graphics editor (with some text and vector graphics capabilities) published by Adobe Systems. ... Microsoft Corporation, (NASDAQ: MSFT, HKSE: 4338) is a multinational computer technology corporation with global annual revenue of US$44. ... Windows Explorer running on Windows Vista Windows Explorer running on Windows XP Windows Explorer is an application that is part of modern versions of the Microsoft Windows operating system that provides a graphical user interface for accessing the file systems. ... In Microsoft Windows, a shell extension is a computer programme that integrates itself into Windows Explorer (the shell. ... API may refer to: In computing, application programming interface In petroleum industry, American Petroleum Institute In education, Academic Performance Index This page concerning a three-letter acronym or abbreviation is a disambiguation page — a navigational aid which lists other pages that might otherwise share the same title. ...

Extension mechanisms can also be found in some operating systems such as with Linux kernel modules. The runtime environment of some programming languages also support extensions, such as PHP with support for extensions that provide an interface to third party libraries, and extensions to offer debugging, profiling, security and performance enhancement. In computing, an operating system (OS) is the system software responsible for the direct control and management of hardware and basic system operations. ... This article is about operating systems that use the Linux kernel. ... In computing, loadable kernel modules, or LKM, are object files that contain code to extend the running kernel, or so-called base kernel. ... In computer science, runtime or run time describes the operation of a computer program, the duration of its execution, from beginning to termination (compare compile time). ... Other listings of programming languages are: Categorical list of programming languages Generational list of programming languages Chronological list of programming languages Note: Esoteric programming languages have been moved to the separate List of esoteric programming languages. ... For other uses, see PHP (disambiguation). ... Debugging is a methodical process of finding and reducing the number of bugs, or defects, in a computer program or a piece of electronic hardware thus making it behave as expected. ... In computer science, performance analysis (also known as program analysis) is the gathering of a programs performance characteristics by measuring events happening in a computer system while running the program. ...

Other popular terms used to denote extensions are add-ons, add-ins or plugins. Add-ons are optional computer hardware or software modules that supplement or enhance the original unit they are adding on to. ... A plugin (or plug-in) is a computer program that can, or must, interact with another program to provide a certain, usually very specific, function. ...

The terms modules and components are also used, but they don't stress the aspect of extending. They are terms to generally describe the structure of programs and can be used for the extended core program as well.

See also

• Extension (Mac OS)
• List of Firefox extensions