Elastic deformation refers to a reversible change in the shape or size of a material when subjected to an external force, which returns the material to its original shape once the force is removed. In this type of deformation, the material can undergo significant distortion or stretching under stress, yet it reverts to its initial state without any permanent alteration or damage. When a force is applied to a material within its elastic limit (also called the proportional limit), the material deforms, but the atomic or molecular structure remains intact. The atoms or molecules within the material temporarily shift from their equilibrium positions due to the stress but return to their original arrangement once the force is removed. This reversible behavior characterizes elastic deformation.