Mac OS 9
operating system
Mac OS 9 is the ninth and final major release of the classic Mac OS operating system for Macintosh computers, developed by Apple. Released on October 23, 1999, it was promoted by Apple as "The Best Internet Operating System Ever", reflecting new Internet features including the Sherlock 2 search tool, integration with the company's iTools online services, and improvements to Open Transport networking.
Mac OS 9 introduced features including an automated Software Update function and multi-user support, but retained the cooperative multitasking and memory architecture of earlier versions of the classic Mac OS, lacking protected memory and full pre-emptive multitasking. It was succeeded by Mac OS X 10.0 in 2001, the first release of the Mac OS X operating system family.
Apple ended development of Mac OS 9 in late 2001 as it transitioned to Mac OS X. The final Mac OS 9 updates focused on compatibility with the Classic Environment and Carbon applications. At the 2002 Worldwide Developers Conference, Steve Jobs opened his keynote with a mock funeral for Mac OS 9, symbolizing Apple's transition to Mac OS X.
Features
Apple billed Mac OS 9 as including "50 new features" and heavily marketed its Sherlock 2 software, which introduced a "channels" feature for searching different online resources and introduced a QuickTime-like metallic appearance. Mac OS 9 also featured integrated support for Apple's suite of Internet services known as iTools (later re-branded as .Mac, then MobileMe, which was replaced by iCloud) and included improved TCP/IP functionality with Open Transport 2.5.
Other features new to Mac OS 9 include:
Integrated support for multiple user accounts without using At Ease.
Support for voice login through VoicePrint passwords.
Keychain, a feature allowing users to save passwords and textual data encrypted in protected keychains.
The public source identifies “Mac OS 9” as operating system. This brief keeps that definition visible, then builds a research path around operating and system.
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This entry incorporates text from “Mac OS 9” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.