Apple will make Mac OS X (10.0) versions of three applications available for download on March 24.
The applications are iMovie2, iTunes and a preview version of AppleWorks 6.1 - Apple's productivity application.
Apple's CEO Steve Jobs said: "Mac OS X is the most important software from Apple since the original Macintosh operating system in 1984. We can't wait for Mac users around the globe to experience its stability, power and elegance."
Late-night sales Mac OS X (10) costs £99 from the Apple Store, it will also go on sale at midnight at London's Micro Anvika on Friday 23 March.
The operating system has come in for criticism for its lack of DVD-player support and CD-authoring abilities. However, it will offer a refined user interface, protected memory, preemptive multi-tasking, symmetric multiprocessing and much-improved graphics - including OpenGL 2D and 3D graphics engines and QuickTime 5 support.
QuickTime 5 will ship for the first time as an integrated feature of the OS.