Windows 95, though still being based on MS-DOS, was its own operating system, using a 16-bit DOS-based kernel and a 32-bit user space.
The first versions of Windows (1.0 through to 3.11) were graphical shells that ran from MS-DOS. The product line evolved in the 1990s from an operating environment into a fully complete, modern operating system over two lines of development, each with their own separate codebase. Microsoft introduced Windows as a graphical user interface for MS-DOS, which had been introduced two years earlier. Microsoft Windows was announced by Bill Gates on November 10, 1983.
See List of Microsoft Windows versions for a tabular view of releases and editions.
