Which Windows version introduced the Taskbar?

Windows 95 was the Windows version that introduced the modern taskbar. It launched on August 24, 1995, with a redesigned desktop shell that placed buttons for open applications along the bottom of the screen and added the Start button and Start menu.

Before Windows 95, Windows 3.1 used Program Manager and displayed minimized applications differently; it did not have the familiar taskbar. The new design made it easier to switch between running programs, launch software, access documents, and reach system settings. It also included a notification area for background utilities, the clock, and volume controls.

Windows NT 4.0 later adopted the Windows 95-style shell for Microsoft's professional and server-oriented NT line, which is why it is sometimes mistaken as the answer. However, NT 4.0 came after Windows 95. Although the taskbar has moved, resized, and gained features across later releases, its defining Windows form began with Windows 95.