Released by IBM in 1984, TopView was a text-mode windowed multitasker for the IBM PC, XT, and AT computer. It featured preemptive multitasking, text-based windowed task sessions, overlapping windows, and supports the use of a mouse. In part, it was one of the reasons why overlapping windows were added to Microsoft Windows 2.0. TopView was later overtaken by DesqView, OS/2, and Windows. For more information, see the Topview 1.00 Software Spotlight.