A ShapeDrawable is a type of drawable in Android that allows developers to create shapes like rectangles, ovals, and lines. It can be customized with various properties such as colors, gradients, and stroke widths. This makes it useful for creating simple graphics and backgrounds in applications. To use a ShapeDrawable, developers typically define the shape and its attributes in code or XML. It can be applied to views, buttons, and other UI elements, enhancing the visual appeal of an app. Overall, ShapeDrawable is a versatile tool for adding custom shapes and styles in Android development.