A WordPress widget performs a unique task, adds functionality to a site, and gives users an easy way to control and customize themes. For example, the RSS widget integrates an external feed, such as a Twitter feed, into a WordPress site. Tag cloud and calendar widgets are also popular. Widgets often come with plugins.
Site administrators can browse available widgets under the Appearance menu item in the Administration Area. Widgets are very easy to install; simply drag-and-drop them into the widgetized areas of the site’s theme. While these areas can vary by theme, they generally include the sidebar, header, and footers. Not all themes support widgets, however. WordPress.com hosting also lacks support for widgets.