Overview
Cairo was announced at the 1991 Microsoft Professional Developers Conference by Jim Allchin. It was demonstrated publicly (including a demo system for all attendees to use) at the 1993 Cairo/Win95 PDC. Microsoft changed stance on Cairo several times, sometimes calling it a product, other times referring to it as a collection of technologies. Bill Gates even attempted on one occasion to describe it as a collection of abstract design goals, strictly denying it had ever been a real operating system project.
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