Windows 3.1

1992 Microsoft operating system version

Windows 3.1 is a consumer-oriented operating system developed by Microsoft, released to manufacturing on April 6, 1992. Unlike its predecessors, which ran as a shell on top of MS-DOS, its 386 Enhanced Mode functioned as a virtual machine monitor virtualizing DOS as a guest. It was the last Windows 16-bit operating system, after which future versions of Windows moved to 32-bit.

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