CSS Animation is a technique used in web design to create dynamic and engaging visual effects on websites. It allows developers to animate changes in CSS properties over time, such as color, size, and position, enhancing the user experience. By using keyframes, designers can define specific points in the animation sequence, making it easy to create smooth transitions. Animations can be triggered by various events, such as hovering over an element or loading a page. CSS Animation is widely supported across modern web browsers, making it a popular choice for adding movement and interactivity without relying on JavaScript or other programming languages.