The Stress-Strain Curve is a graphical representation that shows how materials respond to applied forces. It plots stress (force per unit area) on the vertical axis and strain (deformation or change in shape) on the horizontal axis. This curve helps engineers and scientists understand the mechanical properties of materials, such as their strength and flexibility. As a material is subjected to stress, it initially deforms elastically, meaning it will return to its original shape when the stress is removed. However, if the stress exceeds a certain limit, the material enters the plastic region, where permanent deformation occurs. Understanding this curve is crucial for designing safe and effective structures and products.