A UK-based company D30 has developed a gel with amazing shock-absorbing abilities. The gel reacts to impacts by turning from soft and flexible material to hard protective armour. The technology is already utilised in several industries from sports to defence to help people avoid severe injuries.

4D printing adds a new dimension to 3D printing: time. An object changes its shape or quality as it encounters some external stimuli, such as temperature shifts or contact with water. Currently, research in several laboratories, 4D printing may add programmability to materials and objects.