A Technical History of Apple's Operating Systems - Mac OS X Internals

68 Chapter 1 A Technical History of Apple’s Operating Systems
1.5. SEEKING POWER
As the 1990s began, Apple was making great efforts to overhaul its operating sys-
tem. Of the three “colorful” projects mentioned earlier, Blue, would emerge as Sys-
tem 7.
1.5.1. System 7
When released in 1991, System 7 represented a gigantic leap forward in comparison
to earlier Macintosh systems. Some of its key features included a built-in Multi-
Finder, built-in networking (AppleTalk Phase 2 40), built-in file sharing (Apple-
Share), support for 32-bit memory addressing, a virtual memory implementation,
and a multitude of new technologies 41 such as the following.
• AppleScript—a system-level macro language for automating tasks
• ColorSync—a color management system
• PowerTalk—a collaboration and email software
• QuickTime—a cross-platform multimedia software for viewing and manipulating
video, animations, images, and audio
• TrueType—a font technology
• WorldScript—a multilingual text-rendering engine and programming
interface
The first Macintosh with an MMU was introduced in 1987: the Macintosh II.
Whereas A/UX required an MMU, it was not until System 7 that a Macintosh
operating system would use the MMU. However, the virtual memory sup-
port was only preliminary—features such as protected address spaces,
memory-mapped files, page locking, and shared memory, were not present.
40 AppleTalk Phase 2 was introduced in 1989. It was based on the original version of AppleTalk, but
included several improvements and performance enhancements.
41 Some of these technologies were not bundled with the first release of System 7.