Several billion dermal display nanorobots residing in the epidermis of a human hand can be used as display screens to access real-time physiological information or other stored data, as described byĀ Robert FreitasĀ inĀ Section 7.4.6.7Ā ofĀ Nanomedicine, Vol. I. In this third of four images, the fully visible dermal display screen (in background) shows a clear representation of the concentration and kinds of in vivo nanorobots, to the approval of the user (in foreground).