About
Windows 3.0 was the breakout success that Microsoft had long hoped for. At the time they were partnering with IBM with the OS/2 project. However they didn't want to have such a large 'break' with their main product of the time MS-DOS so they kept on looking for ways to improve on it. Microsoft had become enamored with the new Intel i386 CPU, and wanted to build a great 32bit environment. While IBM had insisted OS/2 support the 16 bit i286 CPU, Microsoft was free to make improvements to it's current realmode 16bit environment Windows.
On the way to Windows 3.0 there was work done on the kernel to support limited multitasking (cooperative) in the 2.0 series, culminating with a 286 version of Windows 2.0 that could run more then one MS-DOS session, although it was very unstable, and a version for the 386 that could run full multiple dos machines (VDM's) within the 16bit constraints. Expanding on this work, the next logical step was to get Windows to execute in protected mode.
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