Fractal: any of various curves or shapes that repeat themselves at any scale on which they are examined.
Fractal shapes are found throughout nature: the growth patterns of plants and veins, the swirling shapes of sea shells, the patterns in eddies of water... so many things in nature exhibit evidence of fractal geometry... including the spiral nebula!
More recently, thanks so increased processor speeds, fractal equations have made their way into graphic software applications adding a level of realism to computer generated imagery. My favorite: Kai's Power Tool 5, Fraxsplorer.
Here is a link to some superior galleries of computer generated fractals as well as the FREE software that was used to create them:
http://parkenet.org/jp/fractvty.htm
I have never seen fractals expressed in freehand art other than works by M.C.Esher and studies of wind and water by Leonardo da Vinci. Both of whom were generating fractal before they even had a name!
Of course, I am not on their level by any means! But these repeating shapes and curves have been apparent to me since I was a child. It was only recently that I discovered there was a name and theory behind them. Since I now have a better understanding of them they have been making appearances in my art.
Example: the rounded triangular shapes each contain 3 more triangular shapes that if rounded could each contain a copy of the original shape. And each of those would contain 3 more triangular shapes, etc...
I don't just copy these patters from a book. They just reveal themselves to me. I've found I can discover a fractal patters that fits into nearly any shape. It's fun and inspiring to know that the universe contains such beauty and order even where it is not apparent.
I'm sure that was more of an explanation than you required! Thanks for the positive feedback.