Macintosh clones

A Macintosh clone is a personal computer made by a manufacturer other than Apple, using (or compatible with) Macintosh ROMs and system software.

The Apple II and IBM PC computer lines were "cloned" by other manufacturers who had reverse-engineered the minimal amount of firmware in the computers' ROM chips and subsequently legally produced computers which could run the same software. These clones were seen by Apple as a threat, as Apple II sales had presumably suffered from the competition provided by Franklin Computer Corporation and other clone manufacturers, both legal and illegal. At IBM, the threat proved to be real: most of the market eventually went to clone-makers, including; Compaq, Leading Edge, Tandy, Kaypro, Packard Bell, Amstrad in Europe and dozens of smaller companies, and in short order IBM found it had lost control over its own platform.

Apple eventually licensed the Apple II ROMs to other companies, primarily to educational toy manufacturer Tiger Electronics, in order to produce an inexpensive laptop with educational games and the AppleWorks software suite, the Tiger Learning Computer (TLC). The TLC lacked a built in display. Its lid acted as a holster for the cartridges which stored the bundled software, as it had no floppy drive.

Wary of repeating history and wanting to retain tight control of its product, Apple's Macintosh strategy included technical and legal measures which rendered production of Mac clones problematic. The original Macintosh system software contained a very large amount of complex code, which embodied the Mac's entire set of APIs, including the use of the GUI and file system. Through the 1980s and into the 1990s, much of the system software was included in the Macintosh's physical ROM chips. Therefore, any competitor attempting to create a Macintosh clone without infringing copyright would have to reverse-engineer the ROMs, which would have been an enormous and costly process without certainty of success. Only one company, Nutek, managed to produce "semi-Mac-compatible" computers in the early 1990s by partially re-implementing System 7 ROMs.

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