Windows 1.0 BYTE demo

The Windows 1.0 BYTE demo is an early demonstration of Microsoft Windows that was shown in the December 1983 issue of BYTE Magazine. The demo itself was produced in September 1983 and was likely shown to members of the press shortly after its compilation. A photograph of a floppy disk containing the demonstration was posted to Twitter by ReflectiaX on 9 March 2022, although he later revealed that the original disk had been demagnetized to the point where data recovery is not possible. Other copies of the disk are supposed to be in circulation. As of 2022, it is the earliest known of Microsoft Windows.

The interface is very similar to Microsoft's DOS applications such as Word and Multiplan which were also released or in development at the time, with a command bar at the bottom of the screen, and featured overlapping windows that were later replaced by tiling windows. It remains unclear whether the build and applications demonstrated were actually fully functional or just cleverly crafted to create an illusion of a working system.