Cross-Browser Compatibility for Designers

I’ve already written an article on my own frustration with Internet Explorer 6 as a designer / developer and posted a simple browser-sniffer script that redirects IE 6 users to a separate page on your site. This article focuses on testing your designs on other browsers, running on different operating systems. Besides testing your web layouts for discrepencies in your margins, paddings, font variations, other things to look for are transparency issues especially when working with transparent PNG files.