A force acting on an object may cause the shape of an object to change.

Elastic objects can store elastic potential energy if they are stretched or squashed. For example, this happens when a catapult is used or a spring is stretched.

Objects can also store elastic potential energy when they are squashed.

For example, this happens when a squash ball is dropped onto a hard surface or a stress ball is squeezed.

Work is done on an object when its shape changes.

When work is done, energy is transferred, and this energy is stored as elastic potential energy. When the object returns to its original shape, the stored elastic potential energy is released.