Soap bubbles are thin films of liquid that form when soap is mixed with water. The soap molecules reduce the surface tension of the water, allowing it to stretch and form a bubble. When light hits the bubble, it creates colorful patterns due to the interference of light waves reflecting off the inner and outer surfaces of the film. Bubbles can vary in size and shape, often appearing spherical due to surface tension pulling the liquid into the most efficient form. They are commonly seen in everyday life, such as in bubble baths or when blowing bubbles with a bubble wand.