About
A preprocessor takes an arbitrary source file and converts it into something that the browser understands.
Preprocessors implements features that browser doesn't support natively such as:
- CSS selectors nesting
- module (template)
- import without http request. See CSS - @import rule
- vendor prefix grouping
- Inheritance of properties (Same property for a message but different color for waning, info)
- Mathematics Operators
In-browser preprocessor editing can be done with the following browser features:
- local file editing (workspaces)
- automatic reloading
Articles Related
Example
- Sass,
- and Stylus.