NeXTSTEP NeXTSTEP used a hybrid kernel that combined the
Mach 2.5 kernel developed at
Carnegie Mellon University with subsystems from
4.3BSD. NeXTSTEP also introduced a new windowing system based on
Display PostScript that intended to achieve better
WYSIWYG systems by using the same language to draw content on monitors that drew content on printers. NeXT also included
object-oriented programming tools based on the
Objective-C language that they had acquired from
Stepstone and a collection of Frameworks (or Kits) that were intended to speed software development. NeXTSTEP originally ran on
Motorola's
68k processors, but was later ported to
Intel's
x86,
Hewlett-Packard's
PA-RISC and
Sun Microsystems'
SPARC processors. Later on, the developer tools and frameworks were released, as
OpenStep, as a development platform that would run on other operating systems.
Rhapsody On February 4, 1997, Apple acquired NeXT and began development of the
Rhapsody operating system. Rhapsody built on NeXTSTEP,
porting the core system to the
PowerPC architecture and adding a redesigned user interface based on the
Platinum user interface from
Mac OS 8. An emulation layer called
Blue Box allowed Mac OS applications to run within an actual instance of the Mac OS and an integrated
Java platform. The Objective-C developer tools and Frameworks were referred to as the
Yellow Box and also made available separately for
Microsoft Windows. The Rhapsody project eventually bore the fruit of all Apple's efforts to develop a new generation Mac OS, which finally shipped in the form of
Mac OS X Server.
Mac OS X At the 1998
Worldwide Developers Conference (WWDC), Apple announced a move that was intended as a response to complaints from Macintosh software developers who were not happy with the two options (Yellow Box and Blue Box) available in Rhapsody. Mac OS X would add another developer
API to the existing ones in Rhapsody. Key APIs from the
Macintosh Toolbox would be implemented in Mac OS X to run directly on the BSD layers of the operating system instead of in the emulated Macintosh layer. This modified interface, called
Carbon, would eliminate approximately 2000 troublesome API calls (of about 8000 total) and replace them with calls compatible with a modern OS. At the same conference, Apple announced that the Mach side of the kernel had been updated with sources from the
OSF MK 7.3 (Open Source Foundation's MK operating system) and the BSD side of the kernel had been updated with sources from the
FreeBSD,
NetBSD and
OpenBSD projects. At the 1999 WWDC, Apple revealed
Quartz, a new
Portable Document Format (PDF) based windowing system for the operating system that was not encumbered with licensing fees to
Adobe like the Display PostScript windowing system of NeXTSTEP. Apple also announced that the Yellow Box layer had been renamed
Cocoa and began to move away from their commitment to providing the Yellow Box on Windows. At this WWDC, Apple also showed Mac OS X booting off of a
HFS Plus formatted drive for the first time. The first public release of Mac OS X released to consumers was a
Public Beta released on September 13, 2000. ==References==