[citation][nom]MrF430[/nom]... when MAC's offerings all seem to be service packs as well no? OS X Cheetah (10.0), Puma (10.1), Jaguar (10.2), Panther (10.3), Tiger (10.4), Leopard (10.5), and Snow Leopard (10.6); all of those happen to be service packs as well, and the last I checked SP1,2,3 etc for XP and Vista were all free, how much did Apple charge you again?. Maybe I'm just crazy but OS9 and OS10 are indeed 2 different OS's are they not? OS 10.0 - 10.6 seem to be the same OS with a few updates, no?[/citation]No.
Mac OS X has had 10.0, 10.1, 10.2, 10.3, 10.4, 10.5, and 10.6. WinNT and descendants has had NT 3.1, 3.5, & 4.0, Win2k, XP, Vista, and Win7. 7 versions of each.
Mac OS X 10.0 is roughly comparable to NT 3.1, each was the first release of a completely new operating system, both were primarily for developers.
Mac OS X 10.1 (free update) and NT 3.5 were notable improvements, but still largely for developers and technology fans, not mainstream users or production environments.
Mac OS X 10.2 and NT 4 were the first versions well suited to a production environment. These had fairly stable servers and were heavily used by IT pros and power users.
Mac OS X 10.3 and Win2k were the first versions well suited for mainstream users.
Mac OS X 10.4 and WinXP had significant improvements in security, managability, APIs and user interface. These were widely adopted by mainstream users.
Mac OS X 10.5 is much like Vista, lots of new features, updated APIs, and a revamped UI. Both have significantly higher system requirements than their predecessors.
Mac OS X 10.6 (nearly free $29) is roughly equivalent to Win7, mostly tuning the infrastructure and performance, not as many new features or UI updates.
Both have gone through significant changes in user interface, API, infrastructure, and security in the intervening versions. Both moved from 32-bit to 64-bit. Both originally ran on CPU architectures other than what the now reguire (Mac OS X was originally PPC only, NT originally supported x86, Alpha, Sparc, and MIPS), and both supported multiple processor architectures in some versions. Both provided a compatibility layer for older software.
Mac OS X 10.0 came out in March 2001, 10.6 is due in September 2009. NT 3.1 came out in July 1993, Win7 is due in October 2009, so the timeline for Mac OS X is significantly compressed vs Windows, but the evolution and versions have been very similar in capabilities in differences.