Information:-Mac OS 9 2012 - the latest version of the "classical? Macintosh Operating System (Mac OS), Apple presentation October 23, 1999, shortly before the release of Mac OS X. During the presentation, in Mac OS 9, it was announced "50 new features, "including the possibility of a 128-bit encryption and Sherlock 2. During the presentation, in Mac OS 9, it was announced" 50 new features, "including the possibility of a 128-bit encryption and Sherlock 2.