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This version of Windows was the first to be pre-installed on hard drives by PC-compatible manufacturers. Zenith Data Systems had previously shipped all of its computers with Windows 1.0 or later 2.x on diskettes but committed early in the development of Windows 3.0 to shipping it pre-installed. Indeed, the Zenith division had pushed Microsoft hard to develop the graphical user interface because of Zenith's direct competition with Apple in the educational market. However, Zenith PCs had to run a proprietary OEM version of Windows because they used hard disks with 1024 byte sectors (instead of the normal 512 bytes) and could not use the standard SWAPFILE.EXE
In December 1990, Microsoft released an updated Windows 3.0 with bug fixes and improved ability to move pieces of data greater than 64k (the original release could only manipulate one segment of RAM at a time).
Windows 3.0 was not available as a run-time version, as was the case with its predecessors. A limited-use version of Windows 2.x was often bundled with other applications (i.e. Ami Pro) due to the low market penetration of Windows itself. It again was unsupported after December 31, 2001.
Standard retail and OEM distributions of Windows 3.0 were on high density 1.2MB and 1.44MB floppy disks. A 720k version was also offered, and a 360k edition could be ordered from Microsoft. Fully installed, Windows 3.0 used 5MB of hard disk space.
Read more about this topic: Windows 3.0