There are five major points on a typical metal's stress-strain graph. The first is the limit of proportionality. Prior to this point, the stress strain graph tends to be a straight line, and the Young's modulus can hence be found up to this point. After this, the material no longer follows Hooke's law, but still stretches elastically, and would return to its original shape, until the second major point, the elastic limit. After this point, the material no long returns to its original shape when stretched, and now deforms plastically. The next point is the yield point, where the internal atomic structure of the material breaks down, and there is hence a large amount of extension for minimal stress increase. The fourth point is then the ultimate tensile stress (UTS), which is the maximum stress a material sample can withstand overall. The final point is the point of breaking stress or fracture, where the material can no longer sustain any more increases in stress and breaks, and is where the graph ends.