August 13, 2002: Jaguar Released

Jaguar was the third or fourth iteration of Mac OS X the public was privy to, depending on whether or not you count the beta as a legitimate release. Personal counting preferences aside, Jaguar was the first version of OS X that most users found usable on a day-to-day basis. 

Jaguar was much improved over OS 10.1, the latest cat featured improved performance and a long list of other very welcome changes including: improved mail, improved USB support and, most importantly a decided lack of a reasons to boot in classic. 

Most users, with enough investment in X capable programs could avoid using classic altogether when Apple released the first ready for prime time version of OS X, known as Jaguar on August 13, 2002.