There are many web developers that make their custom design using standards XHTML and CSS codes. Nowadays we have many browsers using standards from W3C: Mozilla Firefox, Opera, Safari, Google Chrome.
When I develop a website, I find problems with IE6. There are many people that uses IE6 without upgrading to IE7, so, we have to check our website to works also with a non standard browser: Internet Explorer 6.
Internet Explorer 6 (IE6), not support fully CSS and has a problem loading PNG with Alpha transparency.

There are many CSS tricks to make IE6 compatible with PNG Alpha and other CSS codes, but every webdesigner must spend its time to develop a custom code working only for IE6 and using CSS Conditional Tags.
Why spend so many times to develop for IE6?
Fortunately, a Javascript Genius, Dean Edwards wrote a script called IE7. This amazing piece of code uses JavaScript to make Internet Explorer 5 and 6 behave like a standards-compliant browser.
First of all, you must download Ie7.js (1150) or Ie8.js (782).
Upload these files in website document root, and apply the code below.