What is a CSS Preprocessor?

A CSS preprocessors are scripting language that are extend the CSS capabilities and then compiles it into regular CSS, there are many CSS preprocessors to choose from, Most of CSS preprocessor are having some features that don't exist in pure CSS, those feature and structure are make more readable, easier to maintain and light weight.

A preprocessors extend CSS with variables, operators, interpolations, functions, mixing many more reused assets we can use it on preprocessors. LESS, SASS and Stylus are the well known preprocessors in market.

Before flexbox CSS layout module, there were following layout modules are available:

  • Block
  • Inline and inline-block
  • Positioning of div using position

The flexbox layout module target to providing a more efficient way to manage layout, and make it more easier to design structure without having to float and positioning, The container having unknown or/and dynamic width, it will distribute space among the items in the container.