The Apple Lisa was a personal computer designed at Apple in the early 1980s

Sep 18, 2008 13:28 GMT  ·  By

Around 1982, Steve Jobs (currently chief exec at Apple Inc.) was forced out of the Lisa project. While he went on to join the Macintosh project, the Lisa had been released to the public. Contrary to popular belief, the Macintosh is not a direct descendant of Lisa, although the similarities between the two systems were striking.

The Apple Lisa was indeed a personal computer designed at Apple Computer Inc. during the early 1980s. The Lisa project was started at Apple in 1978 and evolved into a project to design a powerful personal computer with a graphical user interface (GUI) that would be targeted toward business customers. The main thing that differentiated Lisa from the Macintosh was that Lisa could run multiple applications at the same time, an ability known as “multitasking,” while the Mac would only be able to fire up one program application at a time. In fact, the Lisa was so much more advanced that it could have as many as 16 programs running simultaneously, displaying their respective windows on the desktop. Also great about the Lisa was that it boasted a real Graphical User Interface (GUI), with icons for everything a person would keep stored on their hard drive, something that other OSes didn't.

The Lisa operating system featured cooperative (non-preemptive) multitasking and virtual memory - extremely advanced features for a personal computer at that time. The use of virtual memory coupled with a fairly slow disk system made the system performance seem sluggish at times.

The Lisa was a more advanced (and far more expensive) system than the Macintosh thanks to its built-in protected memory, cooperative multitasking, a generally more sophisticated hard disk based operating system, 2 megabytes of RAM, expansion slots, a larger higher resolution display and many other impressive abilities. Based in part on advanced elements from the failed Apple III SOS operating system released three years earlier, the Lisa also organized its files in hierarchal directories, making it practical to use large hard drives. The Macintosh would eventually adopt this disk organizational design for its HFS filing system. But it would be many years before several of those features would be brought to the Macintosh. For example, protected memory did not arrive until Mac OS X was out in 2001.

Back to the old Macintosh, although it featured a faster 68000 processor (7.89 Mhz), as well as sound output capabilities, the complexity of the Lisa operating system made it a better system overall. However, its impressive abilities also took their toll on the 5 MHz Motorola 68000 microprocessor, making the system feel sluggish, particularly when scrolling in documents.

Although there were obvious similarities between the systems and the final revision (even the rainbow Apple logo was stamped on it), the Lisa 2/10 was only later modified and sold as the Macintosh XL. The Macintosh XL shipped pre-installed with MacWorks XL, a Lisa program that allowed 64K Macintosh ROM emulation. The Lisa 2/10 was sold with the Lisa OS only.