Source: TechTuts.com
Introduction




Combining HTML and CSS is an basic, but essential step to creating great templates, websites, and many other customizable scripts. CSS, or Cascading Style Sheet, allows you to change the style of multiple elements by editing a single piece of coding, rather than editing each HTML element. There are two ways to include CSS in a HTML file, internally and externally. Internal CSS is displayed in the head of a document, while external CSS is links from a separate file. Now that you know the basic idea of CSS, let's begin by adding CSS to an HTML document.