Users control their Windows computer by its graphical user interface (or GUI for short). It only needs a keyboard "or" a mouse to work. In later versions, a touch screen works as well. However, using both a keyboard and a mouse makes many tasks easier. By clicking a few buttons on the screen, Windows helps keep your files safe, and easier to change and move. Versions of Windows after 2005 make it even easier for some users with disabilities because these versions have touch screens. For use of a touch screen, some mobile devices come with Windows. Tablet computers and smartphones such as Microsoft Surface and Microsoft Lumia use Windows.