Form comes with a fairly quick on-screen previewer in grey scale.
These shapes can be mutated, mutations can be selected on screen and saved, or new mutation created based on the selected shape. In normal mode the preview screens can be saved as gif. For qulaity rendering some other sort of output must be generated. It is also possible to morph between different mutations, saving each screen to produce an animation. These L-systems, which to me seem very abstract, can produce quite intricate shapes.