Interference patterns occur when two or more waves overlap and combine, resulting in a new wave pattern. This phenomenon is commonly observed with light waves, sound waves, and water waves. When waves meet, they can either reinforce each other, creating brighter or louder areas, or cancel each other out, leading to darker or quieter regions. A classic example of interference patterns is the double-slit experiment, where light passes through two closely spaced slits, producing alternating bright and dark bands on a screen. This pattern demonstrates the wave nature of light and is fundamental in understanding concepts like wave-particle duality.