In UX, Animation Design (or motion design) is the use of moving elements or transitions to enhance the user interface and experience. Animation can provide feedback, show causality, and guide user attention. For example, a slight bounce on a button press indicates it’s been clicked, or a loading spinner animates to show that a process is underway. Animations can also help make transitions smoother, such as sliding a menu in from the side or fading elements in and out. A well-designed animation can improve usability by making an interface feel responsive and alive (e.g., highlighting a field with a shake when a form input is invalid, mimicking the gesture of saying “no”). However, designers must use animation thoughtfully — it should serve a purpose (feedback, instruction, delight) without distracting or slowing down the user. In summary, animation design enhances user experience by visually communicating status and change in an interface.