A single declaration block would be made of a single or multiple pair of properties and values. For example the following statement describes a style sheet; that consist of a declaration block with a single pair of property and value.

We are going to learn how to write our first basic CSS based HTML/XHTML page. The first thing to keep in mind is; we use HTML/XHTML to organize content into meaningful and logical segments or sections (data and information). We use CSS to make that content look great (layout and presentation).