Fractal generated dendritic patterns. Some mathematical rule-patterns can mimic patterns in nature including the mathematics of symmetry, waves, meanders, and as here, the dendritic patterns characteristic of forked lightning. Fractals are mathematical patterns that are scale invariant. This means that the shape of the pattern does not depend on how closely you look at it. Self-similarity is found in fractals. Other examples of natural fractals are coast lines and tree shapes, which repeat their shape regardless at what magnification you view them. Lightning is a sudden electrostatic discharge during an electric storm between electrically charged regions of a cloud, between that cloud and another cloud, or between a cloud and the ground. The charged regions within the atmosphere temporarily equalize themselves through a lightning flash.