CSS stands for Cascading Style Sheets
CSS defines how HTML elements are to be displayed
Styles were added to HTML 4.0 to solve a problem
CSS saves a lot of work
External Style Sheets are stored in CSS files
CSS Solved a Big Problem
HTML was NEVER intended to contain tags for formatting a document.
HTML was intended to define the content of a document, like:
<h1>This is a heading</h1>
<p>This is a paragraph.</p>
When tags like <font>, and color attributes were added to the HTML 3.2 specification, it started a nightmare for web developers. Development of large web sites, where fonts and color information were added to every single page, became a long and expensive process.
To solve this problem, the World Wide Web Consortium (W3C) created CSS.
In HTML 4.0, all formatting could (and should!) be removed from the HTML document, and stored in a separate CSS file.
CSS Saves a Lot of Work!
The style definitions are normally saved in external .css files.
With an external style sheet file, you can change the look of an entire Web site by changing just one file!