Conditional comments

Conditional comments have the same syntax as an HTML comment (<!-- -->), but they only work on the Internet Explorer browser (IE). Despite the fact that the technique isn't used on the web nowadays, I still keep it here to remind us of what we had to deal with many years ago.

The content inside the comments are only available on IE 5-9, and are ignored by other browsers. In the older versions of IE, starting from IE 10, the syntax is disabled.

<!--[if IE]>Only IE sees this<![endif]-->

You are able to add some constraint to restricts the IE versions, for example:

<!--[if IE 8]>Only IE 8 sees this<![endif]-->

<!--[if gte IE 8]>Only IE 8 and higher versions see this<![endif]-->

<!--[if lte IE 8]>Only IE 8 and lower versions see this<![endif]-->

The special characters indicating the IE versions are listed as following:

You can apply styles or fixes for a given IE version such as

<link href="styles.css" rel="stylesheet" />

<!--[if IE 8]>
    <link href="fix-ie8.css" rel="stylesheet" />
<![endif]-->

<!--[if IE 9]>
    <link href="fix-ie9.css" rel="stylesheet" />
<![endif]-->

The styles.css file contains the styles working for modern browsers whereas fix-ie8.css and fix-ie9.css files provide the fixes for IE 8 and IE 9 respectively.