Deciduous teeth, also known as baby teeth or primary teeth, are the first set of teeth that develop in children. They typically begin to emerge around six months of age and are usually fully formed by age three. There are 20 deciduous teeth in total, which include incisors, canines, and molars. These teeth play a crucial role in a child's development, helping with chewing food and forming speech. Deciduous teeth eventually fall out, making way for permanent teeth that will last into adulthood. The process of losing baby teeth usually starts around age six and continues until about age twelve.