Widget engine

A software widget is a relatively simple and easy-to-use software application or component made for one or more different software platforms.

A desk accessory or applet is an example of a simple, stand-alone user interface, in contrast with a more complex application such as a spreadsheet or word processor. These widgets are typical examples of transient and auxiliary applications that don't monopolize the user's attention.

On the other hand, graphical control elements (GUI "widgets") are examples of reusable modular components that are used together to build a more complex application, allowing programmers to build user interfaces by combining simple, smaller parts.

Because the term, and the coding practice, has been extant since at least the 1980s, it has been applied in a number of contexts.

A Graphical control element (GUI widget) is part of a graphical user interface (GUI) that allows a computer user to control and change the appearance of elements for operating a software application. In this context a widget may refer to a generic GUI element such as a check box, to an instance of that element, or to a customized collection of such elements used for a specific function or application (such as a dialog box for users to customize their computer screen appearances). A Widget toolkit is a set of programming tools that help developers reuse GUI widgets to build a user interface.

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