What are SourceMaps? Basically, it maps the code in your minified/obfuscated/compiled file to the original source code.
The SourceMap is a separate file that can be provided that will give general descriptions to help the browser map the files back to the original codebase. That way, if you have issues in the compiled code, you step through the code, and the browser knows exactly where to put you in the debug code. How sweet is that?
Obviously, I didn’t provide a ton of information on how to use it. Turns out there isn’t much out there yet either. But, there is a nice link on how to use SourceMaps in your browsers at html5rocks. Check that out and it should get you using it pretty quickly. Another downside, it’s not supported by everyone yet. But just you wait, everyone’s going to be jumping on this bandwagon. There are just too many people that will find this useful. So, if you are using some of these minifiers/compilers, put in a request to get that little .smap file added!