Normal blood pressure values are systolic blood pressure <120 mmHg and diastolic blood pressure <80 mmHg. Blood pressure is defined as the pressure exerted on the walls of blood vessels by the blood flowing through them, and may reflect the blood pressure in the physical circulation. Blood pressure is an important vital sign and measurements are influenced by a variety of factors, commonly exercise and emotional stress. The diagnostic criteria for hypertension are systolic blood pressure ≥140 mmHg and diastolic blood pressure ≥90 mmHg measured on three different days without antihypertensive medication. most people have primary hypertension, which is caused by a variety of factors including genetics and the environment, with common factors including heredity, age, smoking, weight gain, and a high-salt diet. Long-term uncontrolled high blood pressure can have a damaging effect on various organs of the body, commonly including the heart, brain, kidneys, retina and other damages. When high blood pressure is detected, it is recommended to consult a regular hospital and take antihypertensive medication under the guidance of a professional doctor.