This is limited aggregation or the lightning effect. This visual is a close up of how lightning is formed with protons and electrons. Diffusion limited aggregation is when a structure grows one particle a time rather than in chunks. Diffusion because the particle is forming in the structure wander randomly, limited because the particles do not come in contact with each other. Additionally, the structure looks the way it does because of the self-similarity phenomenon. This phenomenon is when a structure has small pieces that resemble the final shape. Lightning bolts occur when the amount of electrical charge in the atmosphere overcomes the insulating properties. Technically, there is a momentary crack that breaks through the air. Many cracks form moving down the structure. These cracks are the thunder that we hear. These cracks and pictures are also known as Lycanberg figures. Fun fact, lightning bolts can be four times hotter than the surface of the sun. And lightning bolts can be either positive or negative. Positive are more rare, however they are more powerful than negative. They can strike up to 10 miles away.