Mac OS 9

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. • A Software Update control panel for automatic download and installation of Apple system software updates. • A redesigned Sound control panel and support for USB audio. • Speakable Items 2.0, also known as PlainTalk, featuring improved speech synthesis and recognition along with AppleScript integration. • Improved font management through FontSync. • Remote Access Personal Server 3.5, including support for TCP/IP clients over Point-to-Point Protocol (PPP). • An updated version of AppleScript with support for TCP/IP. • Personal File Sharing over TCP/IP. • USB Printer Sharing, a control panel allowing certain USB printers to be shared across a TCP/IP network. • 128-bit file encryption in the Finder. • Support for files larger than 2 GB. • Unix volume support. • CD Burning in the Finder (introduced in Mac OS 9.1). • Addition of a "Window" menu to the Finder (introduced in Mac OS 9.1) ==Mac OS 9 and the Classic Environment==

PowerPC versions of Mac OS X prior to 10.5 Leopard include a compatibility layer 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 its Finder inside OS X. This requires Mac OS 9 to be installed on the machine, even though most Macs that can run the Classic environment are not necessarily able to boot into Mac OS 9 natively. 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 pieces of software which directly interact with the hardware fail to work properly. In May 2002, at Apple's Worldwide Developers Conference in San Jose, California, Steve Jobs, accompanied by a coffin, held a mock funeral QEMU has experimental support for running Mac OS 9 using PowerPC G4 emulation. == Mac OS 9 and other Mac computers ==

In January 2002, Mac OS X displaced Mac OS 9 as the default operating system for all Macs produced from that point forward beginning with 10.1.2. Despite this, Mac OS 9 continued to be preinstalled on some Macs (especially for Macs equipped with a PowerPC G4 processor) even as late as 2004, despite having its development stopped in late 2001. These Macs, despite coming with Mac OS X by default, also had Mac OS 9 preinstalled alongside the former to allow one to boot into Mac OS 9 natively if the user chooses to do so, ==Other uses==

Aside from Apple-branded hardware, Mac OS 9 can also be operated in other environments such as Windows and Unix. This includes emulation software such as the aforementioned SheepShaver. While it does provide PowerPC processor support, especially on Intel-based Macs, it can only run up to Mac OS 9.0.4 because it does not emulate a memory management unit. QEMU is another piece of software that has PowerPC emulation and is able to run all versions of Mac OS 9 up to Mac OS 9.2.2. ==Version history==

Updates to Mac OS 9 include 9.0.4, 9.1, 9.2.1, and 9.2.2. Mac OS 9.0.4 was a collection of bug fixes primarily relating to USB and FireWire support. Mac OS 9.1 included integrated CD burning support in the Macintosh Finder and added a new Window menu in the Finder for switching between open windows. Mac OS 9.2 increased performance noticeably and improved Classic Environment support. ==Compatibility==