By manipulating the curves, almost any shape can be formed. You can add additional nodes to a path to enable further complexity. Amazingly complex illustrations are thus possible. Since each curve is based upon a mathematical formula, it is resolution independent. And, printing is always at the best quality.
Bitmapped graphics are essentially a grid of dots.
Each dot can be any color allowed by the system. Bitmapped graphics have a fixed resolution. But that does not mean that it will always be the same size. That s not a good thing. A further problem with bitmapped graphics is that as the image resolution increases, the file size increases dramatically.