A blood pressure (BP) apparatus, also known as a sphygmomanometer, is a medical device used to measure blood pressure. There are various types of BP apparatuses, but the most common one consists of an inflatable cuff that is wrapped around the upper arm, a pressure meter (manometer) to measure the pressure in the cuff, and a stethoscope or electronic sensor to detect blood flow sounds (Korotkoff sounds) in the artery when the cuff pressure is released. When taking blood pressure measurements, the cuff is inflated to temporarily stop blood flow in the artery, and then slowly deflated while listening for the sounds of blood flow through the artery. The systolic pressure (the pressure when the heart beats) and diastolic pressure (the pressure when the heart is at rest between beats) are recorded as the pressure in the cuff is gradually decreased.