The Fill section of the Inspector allows you to add and modify the fill properties of the currently selected object. You can create as many fills as you like.
The Cap option determines how the endpoints of strokes with open paths should be rendered.
Butt The end of the stroke is a straight line and does not extend beyond the end vertices. On a zero-length path, the stroke will not be rendered at all.
Round The ends of a stroke are rounded. On a zero-length path, the stroke is a full circle.
Square The ends of a stroke are squared off and extend beyond the end vertices. On a zero-length path, the stroke is a square.