The graph plots stress versus strain. The curve starts at the bottom left of the viewing window at the origin, goes up and to the right with a constant steepness and then goes slightly to the right. The curve then goes up and to the right with increasing steepness, reaches a maximum and then goes down and to the right with increasing steepness and ends at the top right of the viewing window. The nonlinear portion of the graph is highlighted and is marked plastic behavior. The captions on the right are: permanent plastic deformations occur in the material. Strains are termed inelastic since only a portion of the strain will be recovered upon removal of the stress.