The Extra Sidebar Widgets module in Jetpack adds several new widgets to your blog, including RSS Links to Twitter Timelines, Facebook Like Boxes, and more.
In WordPress, widgets allow us to add custom content throughout our sites in areas like sidebars, footers, headers, or anywhere widgets might be enabled in our theme.
When you enable Extra Sidebar Widgets under: Jetpack Widgets > Appearance, you’ll get access to several great new widgets.
Take some time to explore these new widgets and see which ones work best for your site. For more details on how to setup a particular widget head over to the Jetpack documentation page for the Extra Sidebar Widgets.