html5shim vs html5shiv
shim: A compatibility workaround
In computer programming, a shim is a small library which transparently intercepts an API, changes the parameters passed, handles the operation itself, or redirects the operation elsewhere.
Shims typically come about when the behavior of an API changes, thereby causing compatibility issues for older applications which still rely on the older functionality. In such cases, the older API can still be supported by a thin compatibility layer on top of the newer code. Shims can also be used for running programs on different software platforms than they were developed for.
Source: Wikipedia
Don’t lose any more time.
html5shim and html5shiv are exactly the same thing.
To help IE version less then IE9 you can insert the following to the head element of your html pages and thereafter IE will be able to style any “unknown” html element. The “unknown” elements are the new html5 elements
<!--[if lt IE 9]> <script src="http://html5shim.googlecode.com/svn/trunk/html5.js"> </script> <![endif]-->