GEOSGEOS was an operating system from Berkeley Softworks (later GeoWorks). The name was an acronym for "Graphic Environment Operating System." Originally designed for the Commodore 64 and released in 1986, it provided a graphical user interface for the venerable 8-bit computer that closely resembled early versions of Mac OS and included a graphical word processor (geoWrite) and paint program (geoPaint). For many years, Commodore International bundled GEOS with the C64.
Other GEOS-compatible software packages were available from Berkeley or from third parties, including a reasonably sophisticated desktop publishing application called geoPublish and a spreadsheet called geoCalc. While geoPublish was not as sophisticated as Aldus Pagemaker and geoCalc not as sophisticated as Microsoft Excel, the packages provided reasonable functionality, and Berkeley founder Brian Dougherty claimed the company ran its business using its own software on Commodore 8-bit computers for several years.
Enhanced versions of GEOS later became available for the Commodore 128 and Apple II. Written by a group of programmers who cut their teeth on limited-resource video game machines such as the Atari 2600, GEOS was revered for what it could accomplish on machines with 64K of memory and 1 MHz of processing power. Unlike many pieces of commercial software for the C64/128, GEOS took full advantage of many of Commodore's add-ons, such as memory expansion, the enhanced-capacity 1571 and 1581 disk drives, and the C128's high-resolution RGB mode. It also supported a wide variety of printers, including HP PCL printers and the Apple LaserWriter. The ability to print to high-end printers further enhanced its desktop publishing capabilities.
In 1990, GeoWorks released GEOS for IBM PC compatible systems. Sometimes also called GeoWorks Ensemble, it was incompatible with the Commodore and Apple versions but provided numerous enhancements, including scalable fonts and multitasking even on XT and 286-class PC clones and better peformance than Microsoft Windows on 386 and 486 PCs. GEOS was bundled with numerous PCs but like other GUI environments for the PC such as GEM, proved less successful than Windows.
GEOS was later used in a low-end laptop from Brother International and in the Nokia Communicator. A version of it was also marketed in the late 1990s as New Deal Office in hopes of creating a market among owners of 386 and 486 PCs that could not run Windows 95 effectively.