Compare two html files on another html page

I am working on a intranet project that allows our companies web authors to edit the content of our internet site. I am currently trying to get a rollback feature to work. I currently show the current content and backup content code side by side on the page so the author can see what will happen if they do a backup. I was wondering if there was some s开发者_如何学编程ort of comparer (or easy way of implementing one) that will highlight the differences between the html code of the two files.

Thanks

John Resig implemented a nice algorithm for isolating differences between files in javascript, which can be found here.