Infinite CSS animations are a key component in modern web design, offering continuous and dynamic visual elements that enhance user engagement and experience on websites and mobile applications. These animations, which can include rotating carousels, scrolling backgrounds, and progress indicators, operate without a definitive start or end, creating a seamless effect that draws user attention and provides interactive feedback. Utilizing the CSS property animation-iteration-count set to infinite, developers can create diverse animations such as spinning icons or moving backgrounds by defining keyframes and applying them to page elements. While infinite animations can significantly improve user engagement and interactivity, they must be implemented judiciously to avoid performance issues, especially on older devices or slower networks. Best practices include keeping animations simple, ensuring they do not distract from core content, and testing them for compatibility across different browsers and devices. Platforms like LambdaTest assist in verifying the cross-browser functionality and accessibility of these animations, ensuring a consistent and inclusive user experience.