Conditional Internet Explorer Comments

What is "Conditional Comments" ?

This enables you to show or include a dedicated CSS file or Code, Internet Explorer only property.
This is ignored by "validators" and other browsers.
Below is an example how to display a message for Internet Explorer 6 users:

<!--[if lte IE 6]>
<div id="e-report">

Please consider upgrading to a more modern browser.
This website is optimized for Internet Explorer 7, 
Firefox, Opera and Safari, other browsers may or may not work.
We are web developers, designers, we don't want spend our lives fixing IE6 bugs.
Thank You.

</div>
<![endif]-->

<!--[if IE 6]>
Your content for IE 6 comes here ...
<![endif]-->

More about IE "Conditional Comments" ...