URLs and emails will be linked automatically, you don’t need to do anything. To link some text inside a comment to a certain URL, you may use the Markdown syntax:
[Text you want to see](http://url-goes-here.com)
/**
* Prism: Lightweight, robust, elegant syntax highlighting
* MIT license http://www.opensource.org/licenses/mit-license.php/
* @author Lea Verou http://lea.verou.me
* Reach Lea at fake@email.com (no, not really)
* And this is [a Markdown link](http://prismjs.com). Sweet, huh?
*/
var foo = 5;
// And a single line comment http://google.com
@font-face {
src: url(http://lea.verou.me/logo.otf);
font-family: 'LeaVerou';
}
<!-- Links in HTML, woo!
Lea Verou http://lea.verou.me or, with Markdown, [Lea Verou](http://lea.verou.me) -->
<img src="https://prismjs.com/assets/img/spectrum.png" alt="In attributes too!" />
<p>Autolinking in raw text: http://prismjs.com</p>