The WIMP interface incorporates three mouse buttons (named "Select", "Menu" and "Adjust"), context-sensitive menus, window order control (i.e. send to back) and dynamic window focus (a window can have input focus at any position on the stack). The Icon bar (Dock) holds icons which represent mounted disc drives, RAM discs, running applications, system utilities and docked: Files, Directories or inactive Applications. These icons have context-sensitive menus and support drag-and-drop behaviour. They represent the running application as a whole, irrespective of whether it has open windows.