"Squash and stretch" is a fundamental principle of animation that gives objects a sense of weight and flexibility. When an object moves, it can be compressed (squashed) or elongated (stretched) to create a more dynamic and realistic appearance. This technique helps convey emotions and actions, making animations feel more lively and engaging. In practice, when a ball bounces, it squashes upon hitting the ground and stretches as it rises. This principle is not only applicable to animation but also to character design and visual storytelling, enhancing the overall impact of the animated scene.