HTML Conditional Comment(条件コメント)

<link rel="stylesheet" href="/css/style.css" type="text/css">
<!--[if lt IE 7 ]><link rel="stylesheet" href="/css/ie6.css" type="text/css" /><![endif]--> 
<!--[if lt IE 8 ]><link rel="stylesheet" href="/css/ie7.css" type="text/css" /><![endif]--> 
<!--[if gte IE 8 ]><link rel="stylesheet" href="/css/ie8.css" type="text/css" /><![endif]-->

<!--[if IE]>
According to the conditional comment this is IE<br />
<![endif]-->

<!--[if IE 6]>
According to the conditional comment this is IE 6<br />
<![endif]-->

<!--[if IE 7]>
According to the conditional comment this is IE 7<br />
<![endif]-->

<!--[if IE 8]>
According to the conditional comment this is IE 8<br />
<![endif]-->

<!--[if IE 9]>
According to the conditional comment this is IE 9<br />
<![endif]-->

<!--[if gte IE 8]>
According to the conditional comment this is IE 8 or higher<br />
<![endif]-->

<!--[if lt IE 9]>
According to the conditional comment this is IE lower than 9<br />
<![endif]-->

<!--[if lte IE 7]>
According to the conditional comment this is IE lower or equal to 7<br />
<![endif]-->

<!--[if gt IE 6]>
According to the conditional comment this is IE greater than 6<br />
<![endif]-->

<!--[if !IE]> -->
According to the conditional comment this is not IE<br />
<!-- <![endif]-->