The full form of SASS is Syntactically Awesome Style Sheets. SASS is a extension of CSS3 and provides extra. SASS uses line breaks and indentation to determine rule separations much like HAML. SASS can generate CSS files on the fly as you edit them. functionality such as nesting, variables, mixins etc… Sass is processed server-side using Ruby. COMPASS is a CSS framework which uses SASS. COMPASS builds image sprites and includes them in CSS with ease. Easily updated via command line for latest browser prefixes. COMPASS provides a library of valuable CSS3, cross browser mixins, typography patterns.