When you add an object to your drawing, it's given a default outline attribute, a default fill attribute, or both — depending on the type of object drawn. The object's outline is the line that surrounds the object. The fill is the contents of the object (i.e., the color contained within the object). These attributes vary with the type of object and can be changed using the Outline and Fill tools.
Objects with closed paths (e.g., circles, rectangles, and polygons), have both a fill attribute and an outline attribute. Text is given the same fill and outline attributes as open and closed paths, in addition to other attributes such as typeface and style, point size, inter-line spacing, and so on.
Fills
The fill attribute can produce a solid color and a fountain fill. If you like, you can turn either attribute off and leave the other visible. Turning off a rectangle's fill, for example, makes it transparent, allowing objects behind it to show through.
Outlines
Every object you create has an outline that you can manipulate in a variety of ways. You can think of each object as being drawn with a nib of adjustable size, shape, and color. These pen's attributes can apply to a particular object or to all objects you add to your drawing.
How to
To set the default fill
Filling objects