sonunigam (Love Geek):
CSS 2
CSS level 2 was developed by the W3C and published as a Recommendation in May 1998. A superset of CSS1, CSS2 includes a number of new capabilities like absolute, relative, and fixed positioning of elements and z-index, the concept of media types, support for aural style sheets and bidirectional text, and new font properties such as shadows. The W3C maintains the CSS2 Recommendation. *
04-01-11 - 01:30:28

sonunigam (Love Geek): CSS level 2 revision 1 0r CSS 2.1 fixes errors in CSS2, removes poorly-supported features and adds already-implemented browser extensions to the specification. While it was a Candidate Recommendation for several months, on June 15, 2005 it was reverted to a working draft for further review. It was returned to Candidate Recommendation status on 19 July 2007. *
04-01-11 - 01:31:56

sonunigam (Love Geek):
CSS 3
CSS level 3 has been under development since December 15, 2005. The W3C maintains a CSS3 progress report. CSS3 is modularized and consists of several separate recommendations. The W3C CSS3 Roadmap provides a summary and introduction. *
04-01-11 - 01:33:29

sonunigam (Love Geek):
Browser support
Because not all browsers comply identically with CSS code, a coding technique known as a CSS filter can be used to show 0r hide parts of the CSS to different browsers, either by exploiting CSS-handling quirks 0r bugs in the browser, 0r by taking advantage of lack of support for parts of the CSS specifications. *
04-01-11 - 01:34:38

sonunigam (Love Geek): Using CSS filters, some designers have gone as far as delivering different CSS to certain browsers to ensure designs render as expected. Because very early web browsers were either completely incapable of handling CSS, 0r render CSS very poorly, designers today often routinely use CSS filters that completely prevent these browsers from accessing any of the CSS. *
04-01-11 - 01:35:47