What's a Widget?

From Henry Copeland and Megan Mitzel, "The Huge Opportunity for Online Political Ads," New Politics Institute:

Widgets are small modules that can be ... "adopted" independently by users. Widgets blur the line between an ad and a personalized service ... Because a widget provides a service—information, game, tally or newsfeed—users are more likely to interact with it longer than a regular banner ad, thereby increasing brand loyalty and longevity. Allowing users to share the widget with others provides free distribution and placement.