A Substitution Map in which rules are used to operate on a string consisting of letters of a certain alphabet. String rewriting is a particularly useful technique for generating successive iterations of certain types of Fractals, such as the Box Fractal, Cantor Dust, Cantor Square Fractal, and Sierpinski Carpet.

**References**

Peitgen, H.-O. and Saupe, D. (Eds.). ``String Rewriting Systems.'' §C.1 in
*The Science of Fractal Images.* New York: Springer-Verlag, pp. 273-275, 1988.

Wagon, S. ``Recursion via String Rewriting.'' §6.2 in *Mathematica in Action.* New York:
W. H. Freeman, pp. 190-196, 1991.

© 1996-9

1999-05-26