Prone position is a body position where the person lies flat with their chest down and their back up. In anatomical terms, the dorsal side is up, and the ventral side is down.
Prone position is applied in medical settings to help patients with certain conditions and symptoms get relief. For instance, people in respiratory distress are often made to lie flat on their stomach by nurses or by other medical staff.
The opposite position is supine, where the person lies flat on their back.