SMACSS – A must read if you write CSS.

SMACSS (pronounced “smacks”) is more style guide than rigid framework. There’s no library within here for you to download or install. SMACSS is a way to examine your design process and as a way to fit those rigid frameworks into a flexible thought process. It’s an attempt to document a consistent approach to site development when using CSS. And really, who isn’t building a site with CSS these days?! Feel free to take this in its entirety or use only the parts that work best for you. Or don’t use it at all. I understand that this won’t be everybody’s cup of tea. When it comes to web development, the answer to most questions is “it depends”.

Read the full guide here.