Since the discussion about HTML5 Shiv can be condensed into just a few short sentences, the following excerpts from articles provide all the necessary links and introduction to a developer who is savvy with front-end development.

HTML5Shiv is a JavaScript workaround, invented by Sjoerd Visscher, to enable styling of HTML5 elements in versions of Internet Explorer prior to version 9, which do not allow unknown elements to be styled without JavaScript. – Wikipedia

“Heard of Sjoerd Visscher? I would venture to guess you have not; however, what he considered a minor discovery of his is at the foundation of our ability to use HTML5 today.” – The Story of the HTML5 Shiv – Paul Irish

Reference; http://www.paulirish.com/2011/the-history-of-the-html5-shiv/

This script is the defacto way to enable use of HTML5 sectioning elements in legacy Internet Explorer.

https://github.com/aFarkas/html5shiv

(Continued).

“The HTML5 Shiv enables use of HTML5 sectioning elements in legacy Internet Explorer and provides basic HTML5 styling for Internet Explorer 6-9, Safari 4.x (and iPhone 3.x), and Firefox 3.x.”

Usage Example

Using HTML5 Shiv on an HTML5 web page is simple; you may do so with or without installation of the library. Below is an example of how to conditionally include HTML5 Shiv only for Internet Explorer browsers less-than version 9.

<!DOCTYPE html>
<html>
 <head>
  <!--[if lt IE 9]>
  <script src="//cdnjs.cloudflare.com/ajax/libs/html5shiv/r29/html5.min.js"></script>
  <![endif]-->
 </head>
 <body>
 </body>
</html>