Mac OS 9

Also known as OS 9, classic Mac OS 9, Classic 9

operating system

Key facts

Developer: Apple Computer
Os family: Macintosh
Working state: Historic, unsupported
Source model: Closed source
Released to manufacturing: October 23, 1999 ; 26 years ago ( October 23, 1999 )
Latest release: 9.2.2 / December 5, 2001 ; 24 years ago ( 2001-12-05 )
Supported platforms: PowerPC
Kernel type: Microkernel
Default user interface: Apple Platinum
License: Proprietary
Preceded by: Mac OS 8
Succeeded by: Mac OS X 10.0 Mac OS X Server 1.0

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Article

Mac OS 9 is the ninth and final major release of the classic Mac OS operating system for Macintosh computers, made by Apple Computer, Inc. (now Apple Inc.). Introduced on October 23, 1999, it was promoted by Apple as "The Best Internet Operating System Ever", highlighting Sherlock 2’s Internet search capabilities, integration with Apple's free online services known as iTools and improved Open Transport networking.

While Mac OS 9 lacks protected memory and full pre-emptive multitasking, lasting improvements include the introduction of an automated Software Update engine and support for multiple users. It was succeeded by Mac OS X 10.0 in 2001, the first version of the Mac OS X (now macOS) family of operating systems.