CSS is the key presentational technology that is used in website design.
CSS stands for Cascading Style Sheets. CSS is a standard style sheet language
used for describing the presentation (i.e. the layout and formatting) of the web pages.
Prior to CSS, nearly all of the presentational attributes of HTML documents were contained
within the HTML markup (specifically inside the HTML tags); all the font colors, background
styles, element alignments, borders and sizes had to be explicitly described within the HTML.
As a result, development of the large websites became a long and expensive process, since
the style information were repeatedly added to every single page of the website.
To solve this problem CSS was introduced in 1996 by the World Wide Web Consortium (W3C),
which also maintains its standard. CSS was designed to enable the separation of presentation
Now web designers can move the formatting information of the web pages to a separate style sheet which results in considerably
simpler HTML markup, and better maintainability.
CSS3 is the latest version of the CSS specification. CSS3 adds several new styling features and improvements to enhance
the web presentation capabilities.
There are lot more things you can do with CSS.