A prism is a three-dimensional geometric shape that has two parallel, identical bases connected by rectangular or other polygonal faces. The most common type of prism is the rectangular prism, which has six rectangular faces. Prisms can be made from various materials, including glass and plastic, and are often used in optics to refract light. When light passes through a prism, it bends and separates into its component colors, creating a spectrum. This phenomenon is known as dispersion and is commonly demonstrated with a glass prism. Prisms are also used in various applications, such as in cameras, binoculars, and optical instruments.