According to the help files of Captivate:
Widgets are configurable SWF objects created in Flash. Widgets can help provide enhanced interactivity and rich content rapidly
To make it short, a Widget is an external .swf
file that adds an extra feature to the already rich set of tools provided by Captivate. These Widgets are created outside of Captivate in Adobe Flash Professional or in Adobe Flash Builder.
Note
Creating Widgets
Creating Widgets is reserved to developers with knowledge of Flash and ActionScript, so it is beyond the scope of this book. If you have such knowledge, and want to start programming your own Captivate Widgets, make sure you subscribe to Tristan Ward's blog at http://www.infosemantics.com.au/widgetking/. You can also read the following tutorials to get you started: http://blogs.adobe.com/captivate/2009/06/captivate_widgets_tutorial_cre.html and http://blogs.adobe.com/captivate/2010/10/flex-based-widgets.html.
Some Widgets are shipped with Captivate, but the ultimate...