Indeed. Apparently even Powerpoint started out there. From Wikipedia: “The first PowerPoint version (Macintosh 1987) was used to produce overhead transparencies

Indeed. Apparently even Powerpoint started out there. From Wikipedia: “The first PowerPoint version (Macintosh 1987) was used to produce overhead transparencies, the second (Macintosh 1988, Windows 1990) could also produce color 35 mm slides.” Apple invested in the company (Forethought, Inc) before Microsoft aquired it in 1987.