A fill is a color, pattern, or gradient inside an object. You can apply fills to open and closed objects and to faces of Live Paint groups.
The current fill and stroke colors are displayed in the Tools panel.
You can apply one color, pattern, or gradient to an entire object, or you can use Live Paint groups and apply different colors to different faces within the object.
Align Stroke To Center
Align Stroke To Inside
Align Stroke To Outside