By creating a system where an image has a set of genes that help to specify it, and then allowing mutation of those genes, new images can be created. The space of all phenotypic images can be vast and a search technique can help to locate interesting images. The idea is linked to Richard Dawkins's biomorphs. Exponents include William Latham, Karl Sims, Vladimir Pokhilko and Alexei Pajitnov.
A Popular software package for tinkering with genetic art is:
Available from Computer Artworks, http://www.artworks.co.uk/