MACROMEDIA FLASH 8-LEARNING ACTIONSCRIPT 2.0 IN FLASH Manual page 810

Variables
are identifiers that hold values of any data type. Variables can be created, changed,
and updated. The values they store can be retrieved for use in scripts. In the following
example, the identifiers on the left side of the equal signs are variables:
var x:Number = 5;
var name:String = "Lolo";
var c_color:Color = new Color(mcinstanceName);
For more information on variables, see
Vector graphics
describe images using lines and curves, called vectors, that also include color
and position properties. Each vector uses mathematical calculations, instead of bits, to
describe the shape, which allows them be scaled without degrading in quality. Another
graphic type is bitmap, which is represented by dots or pixels.
810 Terminology
"About variables" on page 86.