LSystems are a simple grammar and set of rules which, when repeatedly applied, create new patterns recursively. You can use these to generate space-filling curves such as the Hilbert curve, or fractals such as a sierpienksi triangle, or a dragon curve, etc. One may assign basic "turtle" drawing commands to the symbols of the grammar and generate images. My Python script is set up to generate several of these fractals and curves using very simple rules.
