Definition - What does Windows Desktop Gadgets mean?
Techopedia explains Windows Desktop Gadgets
Windows Vista and Windows 7 came with preloaded widgets such as a calendar, feed headlines, slide show, CPU meter, clock, weather monitor, etc. Widgets were designed to work well with their specific area and tasks. Windows desktop gadgets were available in a sidebar for the Windows Vista version but were configured to be placed anywhere on screen for the Windows 7 version. Along with this, from the Windows 7 version onwards, Windows desktop gadgets were provided with the ability to be resized and the settings to be modifiable. They were running by default in the Windows Vista versions, which reportedly made the boot-up time slower, but this feature was removed from the Windows 7 version. All the Windows desktop gadgets ran in a single sidebar process, and some of the gadgets took up system resources. They had the ability to instantiate any installed ActiveX objects that were enabled through Internet Explorer.
With administrator approval, the gadgets ran with standard user privileges. Windows desktop gadgets were useful for giving information to the user and were easily accessible. These gadgets were considered as a way to personalize the desktop as most of them were visually more appealing than the default one.