Blood pressure is measured using a sphygmomanometer, or blood pressure monitor. It consists of an inflatable cuff that's wrapped around your arm, roughly level with your heart, and a monitoring device that measures the cuff's pressure. The monitor measures two pressures: systolic, and diastolic.

It's important to get an accurate blood pressure reading so that have a clearer picture of the risk for heart disease and stroke. A reading that says blood pressure is lower than it actually is may give you a false sense of security about health.