The plaster has been used for a very long time in the treatment of injuries in the skeletal system including fractures and dislocations. Many disadvantages of the previously used methods were overcome using gypsum. The most commonly used conservative treatment method for the immobilization of the affected area and for the stabilization of fractures is still circumferential plaster casts and various splints made of gypsum. With the expertise of orthopedics and traumatology and the experience acquired by each practice, every physician learns and develops this art. The aim of this article is to compile the historical development of the plaster casts that we use frequently, and to summarize the structural properties that we do not speak often.