Style guide is as the name implies a guide to CSS styling. If you use front-end framework such as bootstrap, you will likely encounter a style guide. Kalei styleguides is one that will help you create your own styleguide. How does it work ?
Well, you download it from their official website. It is using public domain license.
Next, you change their config file located in js/config.js to point to your css file.
It basically parse your CSS file and create a html file. It will also parse any comments and display it on the file.
An example of what it looks like:
This is particularly useful in a collaborative environment. The guide serves as a reference to all developers and designers involved.
So, start using it on your projects. I know I will.
A big thanks to Web Resources Depot for the heads up.