Three decades ago, 3D printing emerged; it uses special printers to produce various models. These models are designed using softwares, then they are printed layer by layer till we get a 3D model. As for the 4D printing technique, it closely resembles 3D printing, adding the fourth dimension, which is time. Adding the dimension of time means transforming from one form to another as a result of the exposure to an external stimulus or a change in the ambient conditions, such as heat, light, humidity, pressure, or electrical charges.