Mac OS 9 and The Classic Environment
PowerPC versions of OS X prior to 10.5 include a compatibility layer (a shell) called Classic, enabling users to run applications and hardware requiring Mac OS 9 from within OS X. This is achieved through running Mac OS 9 without access to Finder inside OS X. This requires Mac OS 9 to be installed on the computer, even if computers that can run the Classic environment are not necessarily able to boot into Mac OS 9. Some Mac OS 9 applications do not run well in Classic, they demonstrate screen redraw problems and lagging performance. In addition, some drivers and other software which directly interacts with the hardware do not work and there is also no access to the OS 9 Finder.
In May 2002, at Apple's Worldwide Developers Conference in San Jose, California, Steve Jobs, accompanied by a coffin, held a mock funeral to announce that Apple had stopped development of Mac OS 9. Mac OS 9.2.2, introduced in December 2001, was the final version of Mac OS 9 and the end of the classic Mac OS.
In June 2005, Jobs announced that the Macintosh platform would be transitioning to Intel x86 microprocessors. Developer documentation of the Rosetta PowerPC emulation layer revealed that applications written for Mac OS 8 or 9 would not run on x86-based Macs. The Classic Environment remains in the PowerPC version of OS X 10.4; however, x86 versions of OS X do not support the Classic environment.
As a workaround for Intel-based Macs, Mac OS 9 can be emulated up to version 9.0.4 by using SheepShaver, a PowerPC emulator. It cannot emulate above 9.0.4 because SheepShaver does not emulate a memory management unit. The PearPC PowerPC emulator does not support Mac OS 9.
Read more about this topic: Mac OS 9
Famous quotes containing the words classic and/or environment:
“For years, they have all been dying
Out, the classic buck-and-wing men”
—James Dickey (b. 1923)
“In a land which is fully settled, most men must accept their local environment or try to change it by political means; only the exceptionally gifted or adventurous can leave to seek his fortune elsewhere. In America, on the other hand, to move on and make a fresh start somewhere else is still the normal reaction to dissatisfaction and failure.”
—W.H. (Wystan Hugh)