Cascading Style Sheets (CSS) is a style sheet language used to describe the presentation semantics — the style and positioning — of elements within a web document written in a simple markup language.
CSS syntax is made up of two parts: the selector and the declaration block inside curly brackets. Inside the declaration block you can have multiple declarations. Each declaration is made of two parts — the property and the value:
p {font-face: Georgia, Tahoma; color: #ffcc00; }
In this example:
p is the selector.
{font-face: Georgia, Tahoma; color: #ffcc00; } is the declaration block.
font-face: Georgia, Tahoma; and color: #ffcc00; are separate declarations.
font-face is a property and Georgia, Tahoma is its value.
color is a second property and #ffcc00; is its value.