JavaFX is a software platform used for creating rich internet applications that can run on various devices, including desktops and mobile devices. It provides a set of graphics and media packages that allow developers to design visually appealing user interfaces with ease. One of the key features of JavaFX is its ability to use a scene graph, which organizes the visual elements of an application in a hierarchical structure. This makes it easier to manage and manipulate the components of the user interface, enhancing the overall user experience.