Fractals are highly complicated and irregular geometric objects.
Fractals are often produced by chaotic dynamical systems. The terms fractal and chaos first appeared in scientific literatures only 25 years ago. But today, fractal and chaos are already household names in the scientific world. They have applications in fields ranging from medicine to earth science, from meteorology to communication, from Wall Street to Disney. Today, one can even find fractals in a textbook for 7 th graders, as well as in almost all calculus books.