Search Settings and Windows Ink Workspace

In Windows 8.1, pressing Windows + W opens a search for settings. You type in a topic, like “mouse”, and it takes you to the relevant Settings page.
In Windows 10, pressing Windows + W opens the Windows Ink Workspace. This is a utility for working with pen-enabled apps. These apps work with a stylus on a touch screen, which enables you to sketch on a tablet. It opens as a sidebar on the right side of the screen and provides quick access to apps like the Sticky Notes, Sketchpad, and Screen Sketch tools, along with quick shortcut tiles to launch pen-enabled apps you recently used.