Editing Apple Lisa (section)

====Lisa OS====
The Lisa [[operating system]] features [[memory protection|protected memory]],<ref>{{cite book |title=Lisa Operating System Reference Manual |page=50}}</ref> enabled by a crude hardware circuit compared to the [[Sun-1]] workstation (c. 1982), which features a full memory management unit. [[Motorola]] did not have an MMU (memory-management unit) for the [[Motorola 68000|68000]] ready in time, so third parties developed their own. Apple's is also the result of a cost-cutting compromise, with sluggish performance. Based, in part, on elements from the [[Apple III]] [[Apple SOS|SOS]] operating system released three years earlier, Lisa's [[disk operating system]] also organizes its files in hierarchical directories. [[File system]] directories correspond to GUI folders, as with previous Xerox PARC computers from which Lisa borrowed heavily. Lisa was designed around a hard drive, unlike the first Macintosh.

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 is almost entirely text-based, though it uses a GUI text editor. The Lisa Office System was eventually renamed 7/7 which refers to the seven supplied application programs: LisaWrite, LisaCalc, LisaDraw, LisaGraph, [[LisaProject]], LisaList, and LisaTerminal.

Apple's warranty said that this software works precisely as stated, and Apple refunded an unspecified number of users, in full, for their systems. These operating system frailties, and costly recalls, combined with the very high price point, led to the failure of the Lisa in the marketplace. NASA purchased Lisa machines, mainly to use the [[LisaProject|LisaProject program]].

In 2018, the [[Computer History Museum]] announced it would be releasing the source code for Lisa OS, following a check by Apple to ensure this would not impact other intellectual property. For copyright reasons, this release does not include the American Heritage dictionary.<ref name="OpenElectronics">{{cite web|last=Ruggeri|first=Luca|title=The Computer History Museum will open source Apple's Lisa OS|date=January 17, 2018|url=https://www.open-electronics.org/the-computer-history-museum-will-open-source-apples-lisa-os/|access-date=May 11, 2020}}</ref> For its 40th anniversary on January 19, 2023, Lisa OS Software version 3.1's source code is available under an [https://www.apple.com/legal/education/apple-school-manager/ Apple Academic License Agreement.]<ref>{{Cite web |last=Hsu |first=Hansen |date=January 19, 2023 |title=The Lisa Was Apple's Best Failure |url=https://spectrum.ieee.org/apple-lisa |url-status=live |archive-url=https://web.archive.org/web/20230120001412/https://spectrum.ieee.org/apple-lisa |archive-date=January 20, 2023 |access-date=January 19, 2023 |website=[[IEEE Spectrum]] |language=en}}</ref><ref>{{Cite web |date=January 19, 2023 |title=CHM Makes Apple Lisa Source Code Available to the Public as a Part of Its Art of Code Series |url=https://computerhistory.org/press-releases/chm-makes-apple-lisa-source-code-available-to-the-public-as-a-part-of-its-art-of-code-series/ |url-status=live |archive-url=https://web.archive.org/web/20230120021048/https://computerhistory.org/press-releases/chm-makes-apple-lisa-source-code-available-to-the-public-as-a-part-of-its-art-of-code-series/ |archive-date=January 20, 2023 |access-date= |website=Computer History Museum |place=Mountain View, CA |language=en}}</ref>