Parametric design is a way to make something (usually a 3D object, like a robot or a piece of furniture) that can be adjusted based on certain parameters or measurements. For example, if you wanted to make a chair, you might enter the length and width of the seat, the length and width of the legs, and the height of the seat into a parametric design program. Then, when you change any of those parameters (length, width, or height), the computer will automatically adjust the shape of the chair to match the new values you input. This way, you can make something that has exactly the measurements you want without having to redraw everything each time.