Related Articles:
March 24, 2001 Mac OS X v10.0 named Cheetah
This version is with slow operation speed and incomplete function list. It is actual existence as a shipping product and considered to be a potential development project.
September 25, 2001 Mac OS X v10.1 named Puma
This version is added new function such as DVD Player. Since Mac users are not satisfied with v10.0, apple released this version for free upgrade from v10.0. It is desperately needed performance improvements.
August 23, 2002 Mac OS X v10.2 named Jaguar
This version has a fresh look and great improvement including:
Quartz Extreme can directly combine image in express card
Brushed Metal Image
iChat becomes the user end of official support AOL Instant-messaging
October 24, 2003 Mac OS X v10.3 named Panther
It offers more special features:
Exposé: new system for window interface operation
Fast User Switching permit another user log in while before logged in user keeps its status
Safari: website browser
Finder renew with metal feeling interface and quick search speed
Sidebars
April 29, 2005 Mac OS X v10.4 named Tiger
Spotlight is a quick content and file search tool based on metadata. It can find out keyword title list according to your need in quite a speed.
Dashboard offers general work Widget once clicking icon
Quartz 2D Extreme is released
Core Image & Core Video can realize instant video and image effect after edited
Extended Attributes launched
October 26, 2007 Mac OS X v10.5 Leopard
Time Machine allows user find back or recover the missing or deleted file or recover to the older version of the file
Spaces would let user to create more than one virtual window or space and let them switch the windows. Users can classify space according to work, entertainment, etc.
Unified UI Theme
Core Animation & Text
Code Signing, FSEvents, DTrace, 64-bit Cocoa, etc.
August 28, 2009 Mac OS X v10.6 Snow Leopard
The biggest new feature in Snow Leopard is support for Exchange, Microsoft's popular e-mail, contact, and calendar server.
Dock: Apple has combined window minimization with Exposé to create a new way of hiding windows that may be more popular than the old one.
QuickTime X features a radically redesigned QuickTime Player application, which some people will love—and many others will hate.
The new Preview also features imaging enhancements. It can now detect images from a USB-connected digital camera or scanner.
These are just some of the more major changes in Snow Leopard. It may be worth trying yourself also.

DVD burn software to convert popular video formats including AVI, MOV, WMV, M4V(without DRM protection), TS, TP, TRP, M2TS, FLV, ASF, MOD, etc. to DVD on Mac, more...
DVD Copy Pro for Mac Copy DVD9 and DVD5 movies. Backup DVD movies to 4 ways including DVD disc, DVD folder, DVD media format and ISO file, more...
Convert various audio and video formats to M4R ringtone formats and offer waveform for precise trim and fade in&out effect available, more...