Mathematics and art are two seemingly disparate fields according to contemporary views, but there are a number of visual artists who make mathematics a focus of their work. There are several themes that have been widely used by mathematical artists. These include polyhedra, tessellations, impossible figures, Mobius bands, distorted or unusual perspective systems, and fractals. Descriptions and examples are provided in this paper, which is intended to some degree as an introduction to the Exhibit of Visual Mathematical Art held as part of Bridges 2001.