about Macintosh OS

Macintosh operating systems (or shortcut Mac OS) is the name for the first operating systems for Macintosh - produced by the company Apple. "The original Mac OS was the first commercially successful operating system which used a graphical user interface."
Very early versions of Mac OS - beginning with System 1.0, Finder 1.0 (January 1984), could only run one application at the time. Already in March 1985 Mac OS included the possibility to switch between multiple applications in System 5. In the year 1988 System 6, which is said it was the best, was released and the user could chose between Finder and MultiFinder (with access to multiple applications). The system was much more stable than the ones before. In late 1991 Version 7 was released and integrated MultiFinder into the basic OS, Versions 8 with the possibility to change the general look of the Finder with a new control panel and 9, which was basically released to make the way to Mac OS X (=ten) and includes itself the possibility to run "within" Mac OS X followed.
In January 1999 Apple released Mac OS X Server 1.0, on March 24th, 2001 was the public release of Mac OS Version 10.0. Mac OS X "brought Unix-style memory management and pre-emptive multitasking to the Mac platform. It is based on the Mach kernel and the BSD implementation of UNIX, which were incorporated into NeXTSTEP, the object-oriented operating system developed by Steve Jobs's NeXT company". Already on September 25th the version 10.1 was released, followed by Mac OS 10.2 (Jaguar) on August 24th, 2002, Mac OS X 10.3 (Panther) on September 24th, 2003 and the latest release Mac OS 10.4 (Tiger) on April 29th, 2005. For 2005 the new version Leopard is planned.
(quoted passages by Wikipedia)

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