By inspecting multiple closely spaced slices, the machine can build up a three-dimensional picture of the patient's insides.

ECONOMIST: Chopping wood

The specimen is then rotated on a mechanised platform as it is exposed to the X-ray beam, in order to build up a three-dimensional picture.

BBC: Hi-tech scans reveal brain of human 'ancestor'

It is able, from the delay between the broadcast of a pulse and its reception in different places, and the strengths of the echoes, to draw a three-dimensional picture of what lies under the ground.

ECONOMIST: Archaeology

The use of either two-dimensional (2D) or three-dimensional (3D) ultrasound to only view the fetus, obtain a picture of the fetus or determine the fetal gender without a medical indication is inappropriate and contrary to responsible medical practice.

FORBES: Virginia's Pre-Abortion Ultrasound Law Medically Unsound-Violates Guidelines of American College Of Obstetricians And Gynecologists