A diene is a type of organic compound that contains two double bonds between carbon atoms. These double bonds can be arranged in different ways, leading to various types of dienes, such as conjugated dienes, where the double bonds are separated by a single bond, and isolated dienes, where the double bonds are separated by more than one single bond. Dienes are important in many chemical reactions, including polymerization, where they can combine to form larger molecules. They are commonly found in natural products and synthetic materials, making them significant in fields like organic chemistry and materials science.