Windows 2.x

Windows 2.x is a graphical personal computer operating system developed by Microsoft. It was said to look almost the same to the first Mac OS and more closely matched Microsoft's pre-release publicity for Windows 1.0.
Windows 2.1x.
Five months after the release of Windows 2.03, Microsoft released Windows 2.10, and after 10 months, Windows 2.11. They were the first versions that required an Intel 80286 or 80386 processor to run.