A 2D shape is a figure that has only length and height as its dimensions. Because 2D shapes lie on a flat surface, they are also known as plane figures or plane shapes. While they have areas, 2D shapes have no volume. In mathematics and physics, a 2D figure is plotted on two axes, namely the x- and y-axes. Circle, triangle, square, rectangle, and pentagon are some of the most common examples of 2D shapes.
Apart from length and height, a 3D shape also has width or depth as its third dimension. They have areas, as well as have volume. A 3D figure is plotted on three axes, namely the x-, y-, and z-axes. Cylinder, pyramid, cube, and prism are some of the most common examples of 3D shapes.
Extensively, these 2D shapes are used to draw simple images or sketch of a simple object. 2D shapes are used to show top view, side view, front view, bottom view in engineering drawings.
3D shapes are used to define the architectural view of an object. 3D shapes are used to draw isometric and orthogonal shapes.