A Beziers curve is defined by a start point, and an end point and 2 tension points. It is possible to draw more than one curve at a time, providing the curves are attached. The PolyBezier function considers the end point of the previous curve as the start point for the next point. The graphics API does not draw filled Bezier curves. It seemed to me that this would be a neat feature to have, so combined Bezier curves with Paths.
Paths are a type of recording device.
Not a sophisticated as metafiles, but decidedly useful. Each canvas can only have one path at a time, and you must create the path before you use it. You then draw, as normal, onto the canvas. Any drawing to the canvas while a path is being recorded is sent to the path, and not to the canvas it self. Once you have created a path, you need to draw the path onto the screen.