GeoWorks: the GUI operating system that once rivaled early Windows
GeoWorks began as GEOS, a graphical operating system for the Commodore 64 built by Berkeley Softworks, known for running efficiently on cheap, low-power hardware. In the early 1990s it was ported to PCs under the renamed GeoWorks, and AOL even built a DOS version of its client using the platform before Microsoft Windows became dominant.