The supine position is a position of the body

Human body

The human body is the entire structure of a human organism, and consists of a head, neck, torso, two arms and two legs.By the time the human reaches adulthood, the body consists of close to 100 trillion cells, the basic unit of life...

: lying down with the face

Face

The face is a central sense organ complex, for those animals that have one, normally on the ventral surface of the head, and can, depending on the definition in the human case, include the hair, forehead, eyebrow, eyelashes, eyes, nose, ears, cheeks, mouth, lips, philtrum, temple, teeth, skin, and...

 up, as opposed to the prone position

Prone position

The term means to lie on bed or ground in a position with chest downwards and back upwards.-Etymology :The word "prone," meaning "naturally inclined to something, apt, liable," has been recorded in English since 1382; the meaning "lying face-down" was first recorded in 1578, but is also referred to...

, which is face down, sometimes with the hands behind the head or neck. When used in surgical procedures, it allows access to the peritoneal, thoracic and pericardial

Pericardium

The pericardium is a double-walled sac that contains the heart and the roots of the great vessels.-Layers:...

 regions; as well as the head, neck and extremities. A study claims that people solve anagrams significantly faster when supine than when standing.