The Lisa operating system featured cooperative (non-preemptive) multitasking and virtual memory, then extremely advanced features for a personal computer. The use of virtual memory coupled with a fairly slow disk system made the system performance seem sluggish at times. Based in part on advanced elements from the failed Apple III SOS operating system released 3 years earlier, the Lisa also organized its files in hierarchal directories, making the use of large hard drives practical. The Macintosh would eventually adopt this disk organizational design as well for its HFS filing system. Conceptually, the Lisa resembles the Xerox Star in the sense that it was envisioned as an office computing system; consequently, Lisa has two main user modes: the Lisa Office System and the Workshop. The Lisa Office System is the GUI environment for end users. The Workshop is a program development environment, and was almost entirely text-based, though it used a GUI text editor. The Lisa Office System was eventually renamed "7/7", in reference to the seven supplied application programs: LisaWrite, LisaCalc, LisaDraw, LisaGraph, LisaProject, LisaList, and LisaTerminal.
Both OS 2 and 3 are included.Compatibility
Modern Computers (Emulation)