2D, or two-dimensional, refers to a space that has only two dimensions: length and width. In a 2D environment, objects can be represented on a flat surface, such as a piece of paper or a computer screen. Common examples of 2D shapes include squares, circles, and triangles, which can be drawn without any depth. In contrast to 3D (three-dimensional) objects, which have length, width, and height, 2D objects lack depth. This means that while you can see the shape and size of a 2D object, you cannot perceive it from different angles as you would with a cube or a sphere. 2D graphics are widely used in art, design, and digital media.