GEOS (''Graphic Environment Operating System'') is a discontinued

operating system An operating system (OS) is system software that manages computer hardware and software resources, and provides common daemon (computing), services for computer programs. Time-sharing operating systems scheduler (computing), schedule tasks for ...

from Berkeley Softworks (later GeoWorks). Originally designed for the

Commodore 64 The Commodore 64, also known as the C64, is an 8-bit computing, 8-bit home computer introduced in January 1982 by Commodore International (first shown at the Consumer Electronics Show, January 7–10, 1982, in Las Vegas). It has been listed in ...

with its version being released in 1986, enhanced versions of GEOS later became available in 1987 for the

Commodore 128 The Commodore 128, also known as the C128, is the last 8-bit home computer that was commercially released by Commodore Business Machines (CBM). Introduced in January 1985 at the CES in Las Vegas, it appeared three years after its predecessor, t ...

and in 1988 for the

Apple II Apple II ("apple Roman numerals, two", stylized as Apple ][) is a series of microcomputers manufactured by Apple Computer, Inc. from 1977 to 1993. The Apple II (original), original Apple II model, which gave the series its name, was designed ...

. A lesser-known version was also released for the Commodore Plus/4. GEOS closely resembles early versions of the classic Mac OS and includes a graphical word processor (geoWrite) and Computer graphics, paint program (geoPaint). A December 1987 survey by the Commodore-dedicated magazine '' Compute!'s Gazette'' found that nearly half of respondents used GEOS. For many years, Commodore bundled GEOS with its redesigned and cost-reduced C64, the C64C. At its peak, GEOS was the third-most-popular microcomputer operating system in the world in terms of units shipped, trailing only

MS-DOS MS-DOS ( ; acronym for Microsoft Disk Operating System, also known as Microsoft DOS) is an operating system for x86-based personal computers mostly developed by Microsoft. Collectively, MS-DOS, its rebranding as IBM PC DOS, and a few op ...

and Mac OS (besides the original Commodore 64's

KERNAL KERNAL is Commodore's name for the ROM-resident operating system core in its 8-bit home computers; from the original PET of 1977, followed by the extended but related versions used in its successors: the VIC-20, Commodore 64, Plus/4, Commodore ...

). Other GEOS-compatible software packages were available from Berkeley Softworks or from third parties, including a reasonably sophisticated

desktop publishing Desktop publishing (DTP) is the creation of documents using dedicated software on a personal ("desktop") computer. It was first used almost exclusively for print publications, but now it also assists in the creation of various forms of online co ...

application called geoPublish and a spreadsheet called geoCalc. While geoPublish is not as sophisticated as Aldus Pagemaker and geoCalc not as sophisticated as

Microsoft Excel Microsoft Excel is a spreadsheet editor developed by Microsoft for Microsoft Windows, Windows, macOS, Android (operating system), Android, iOS and iPadOS. It features calculation or computation capabilities, graphing tools, pivot tables, and a ...

, the packages provide reasonable functionality, and Berkeley Softworks founder Brian Dougherty claimed the company ran its business using its own software on Commodore 8-bit computers for several years.

Development

Written by a group of programmers at Berkeley Softworks, the GEOS Design Team: Jim DeFrisco, Dave Durran, Michael Farr, Doug Fults, Chris Hawley, Clayton Jung, and Tony Requist, led by Dougherty, who cut their teeth on limited-resource video game machines such as the

Atari 2600 The Atari 2600 is a home video game console developed and produced by Atari, Inc. Released in September 1977 as the Atari Video Computer System (Atari VCS), it popularized microprocessor-based hardware and games stored on swappable ROM cartridg ...

, GEOS was revered for what it could accomplish on machines with 64–128 kB of

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memory and 1–2

MHz The hertz (symbol: Hz) is the unit of frequency in the International System of Units (SI), often described as being equivalent to one event (or cycle) per second. The hertz is an SI derived unit whose formal expression in terms of SI base u ...

of 8-bit processing power. Unlike many pieces of

proprietary software Proprietary software is computer software, software that grants its creator, publisher, or other rightsholder or rightsholder partner a legal monopoly by modern copyright and intellectual property law to exclude the recipient from freely sharing t ...

for the C64 and C128, GEOS takes full advantage of many of the add-ons and improvements available for these systems. Commodore's 1351 mouse is supported by GEOS, as are its various RAM expansion units. GEOS 128 also fully supports the C128's 640×200 high-resolution VDC display mode through a compatible

RGB The RGB color model is an additive color model in which the red, green, and blue primary colors of light are added together in various ways to reproduce a broad array of colors. The name of the model comes from the initials of the three ...

monitor. The C64 version of GEOS incorporates a built-in

fast loader A fast loader is a software program for a home computer, such as the Commodore 64 or ZX Spectrum, that accelerates the speed of file loading from floppy disk or Compact Cassette, compact cassette. Floppy disks Fast loaders came about becaus ...

, called ''diskTurbo'', that significantly increases the speed of drive access on the slow

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. GEOS is the first Commodore software that could use a floppy disk as swap space or

virtual memory In computing, virtual memory, or virtual storage, is a memory management technique that provides an "idealized abstraction of the storage resources that are actually available on a given machine" which "creates the illusion to users of a ver ...

. GEOS 128 can take advantage of the C128's enhanced "burst mode" in conjunction with the

1571 Year 1571 ( MDLXXI) was a common year starting on Monday of the Julian calendar. Events January–March * January 11 – The Austrian nobility are granted freedom of religion. * January 23 – The Royal Exchange opens in Lond ...

and 1581 drives. The Commodore version of GEOS uses a

copy protection Copy protection, also known as content protection, copy prevention and copy restriction, is any measure to enforce copyright by preventing the reproduction of software, films, music, and other media. Copy protection is most commonly found on vid ...

scheme that renders users' disks unbootable if it detects that the disk has been illegally duplicated. Via Berkeley's special geoCable interface converter or other third-party interfaces to connect standard

RS-232 In telecommunications, RS-232 or Recommended Standard 232 is a standard introduced in 1960 for serial communication transmission of data. It formally defines signals connecting between a ''DTE'' (''data terminal equipment'') such as a compu ...

Centronics Centronics Data Computer Corporation was an American manufacturer of computer printers, now remembered primarily for the parallel interface that bears its name, the Centronics connector. History Foundations Centronics began as a divisio ...

printers to the Commodore serial bus, GEOS supports a wide variety of printers, including HP PCL printers and the Apple LaserWriter. This ability to print to high-end printers was a major factor in making GEOS a desktop publishing platform. The Apple II version of GEOS was released as

freeware Freeware is software, often proprietary, that is distributed at no monetary cost to the end user. There is no agreed-upon set of rights, license, or EULA that defines ''freeware'' unambiguously; every publisher defines its own rules for the free ...

in August 2003. The Commodore 64/128 versions followed in February 2004. The latest GEOS desktop suite for IBM PC compatibles is Breadbox Ensemble. Revivals were seen in the OmniGo handhelds,

Brother A brother (: brothers or brethren) is a man or boy who shares one or more parents with another; a male sibling. The female counterpart is a sister. Although the term typically refers to a family, familial relationship, it is sometimes used ende ...

GeoBook line of laptop-appliances, and the NewDeal Office package for PCs. Related code found its way to earlier "Zoomer" PDAs, creating an unclear lineage to Palm, Inc.'s later work.

Nokia Nokia Corporation is a Finnish multinational corporation, multinational telecommunications industry, telecommunications, technology company, information technology, and consumer electronics corporation, originally established as a pulp mill in 1 ...

used GEOS as a base operating system for their

Nokia Communicator The Nokia Communicator is a brand name for a series of business-optimized mobile phones marketed by Nokia Corporation, all of which appear as normal (if large) phones on the outside, and open in clamshell format to access a QWERTY keyboard and a ...

series, before switching to EPOC (

Symbian Symbian is a discontinued mobile operating system (OS) and computing platform designed for smartphones. It was originally developed as a proprietary software OS for personal digital assistants in 1998 by the Symbian Ltd. consortium. Symbian OS ...

GEOS versions

* 1986: GEOS for Commodore 64 * 1987: GEOS for Commodore C128, Commodore Plus/4 (unofficial) * 1988: GEOS for Apple II, GEOS V2.0 for Commodore C64, GEOS V2.1 for Apple II * 1989: GEOS V2.0 for Commodore C128 * 2022: GEOS for Atari (unofficial)

Reverse engineering efforts

On August 19, 2016, Michael Steil posted in his blog that the source code for GEOS 2.0 for Commodore C64 had been fully reverse-engineered and suitable for the cc65 compiler suite. The reverse-engineered source code has been made available at

GitHub GitHub () is a Proprietary software, proprietary developer platform that allows developers to create, store, manage, and share their code. It uses Git to provide distributed version control and GitHub itself provides access control, bug trackin ...

.GitHub - mist64/geos: Source code of GEOS 2.0 for the Commodore 64 and 128
/ref>

GEOS products and applications

Dozens of official and third-party applications and other products were produced for GEOS. Among the most important and popular were the following: * geoBASIC * geoCable * geoCalc * geoChart * geoDex * geoDraw * geoFAX * geoFile * geoFont * geoLabel * geoPaint * geoPrint * geoProgrammer * geoPublish * geoSpell * geoWrite * geoWrite Workshop * geoRAM * Writer 64 ( Timeworks)

Reception

Personal Computer World ''Personal Computer World'' (''PCW'') (February 1978 - June 2009) was the first British computer magazine. Although for at least the last decade it contained a high proportion of Windows PC content (reflecting the state of the IT field), the m ...

'' in January 1987 favorably reviewed version 1.2 for the Commodore 64. The magazine approved of geoWrite ("you could easily be fooled into thinking that you were using MacWrite"), geoPaint, fastloader, and documentation, and concluded that "GEOS has given the C64 a complete face-lift and a new lease on life".

References

External links

Breadbox
Home of the GEOS operating system (down, archive
here
at the Internet Archive)

– By Bo Zimmermann
GEOS: The Graphical Operating System
A lengthy review of GEOS and its history {{DEFAULTSORT:Geos 1986 software Operating system families Apple II software Commodore 128 software Commodore 64 software Graphical user interfaces Proprietary operating systems Window-based operating systems