Celluloid is a type of plastic made from cellulose, a natural polymer found in plant cell walls. It was first developed in the mid-19th century and became popular for its versatility and ability to be molded into various shapes. Celluloid is often used in products like film, combs, and buttons due to its lightweight and durable nature. One of the most significant uses of celluloid was in the production of early motion picture film. The invention of motion pictures relied heavily on celluloid's ability to hold images, making it a crucial material in the history of cinema. However, it is highly flammable, which led to the development of safer alternatives over time.