TweenJS is a simple JavaScript library designed for creating smooth animations in web applications. It allows developers to animate properties of objects over time, making it easy to create engaging user interfaces and dynamic visual effects. With its straightforward syntax, TweenJS helps streamline the animation process, enabling quick adjustments and fine-tuning. The library is part of the CreateJS suite, which includes other tools for building rich interactive content. TweenJS supports various easing functions, allowing for more natural movement in animations. This flexibility makes it a popular choice for developers looking to enhance their projects with visually appealing transitions.