Animation can be defined as the moving and changing of objects over time. A simple animation may be moving an object a little bit along a specific trajectory with each frame (direction vector) with a fixed velocity (units per second). In Unity, animation can be implemented by writing simple C# scripts that update an object's transform with each frame Update().

More complex animations can be defined using the Animation panel to draw curves for how object properties change over time. In the following example, the animation moves a ball linearly along the y axis while letting it wobble back and forth a small amount in the other two directions:

Unity also provides a third, even more advanced tool, known as the Animator Controller. This allows you to program more complex animation sequences that respond to specific events and object states. Animator controllers are state machines that determine which animations are currently being played, and blend the animations seamlessly. They can be programmed using a graphic, flow-chart-like visual programming interface, depicted here (source https://docs.unity3d.com/Manual/class-AnimatorController.html):