Scientists have long relied on the power of imaging techniques to help them see things invisible to the naked eye and thus advance scientific knowledge. In medicine, X-ray imaging and magnetic resonance imaging (MRI) have added a level of insight beyond traditional lab tests into the workings of the human body and identification of disease at its earliest stages. Microscopy, which has been in use since the sixteenth century, is now powerful enough to detect, identify, track, and manipulate single molecules on surfaces, in solutions, and even inside living cells
