Both Chinese and European guidelines for hypertension classify blood pressure levels as ideal, normotensive, normal hypertensive, and hypertensive based on the same criteria. Ideal blood pressure is defined as systolic blood pressure <120 mmhg and diastolic blood pressure <80 mmhg; normotension is defined as systolic blood pressure 120-129 mmHg and/or diastolic blood pressure 80-84 mmHg; and normal hypertension is defined as systolic blood pressure 130-139 mmHg and/or diastolic blood pressure 85-89 mmHg. Hypertension is defined as the absence of antihypertensive medication in the presence of Three measurements on the same day revealed a systolic blood pressure ≥ 140 mmHg and/or diastolic blood pressure. Since human blood pressure has significant fluctuations, only when it is not exceeded three times on the same day by repeated measurements can one be identified as having hypertension; in addition, as long as one of the systolic or diastolic blood pressure reaches the standard, one can be identified as having hypertension, for example, blood pressure of 120/90 mmHg and 140/80 mmHg are both considered hypertensive. Depending on the level of elevated blood pressure, hypertension is further classified as grade 1, grade 2 and grade 3. Currently, the clinical diagnosis of hypertension is mainly based on clinic blood pressure. Clinic blood pressure is easy to measure and the relationship between clinic blood pressure and cardiovascular risk has been well documented in evidence-based medical studies. To rule out white-coat hypertension and to detect occult hypertension, out-of-office blood pressure measurements should be performed in conjunction with clinic blood pressure measurements. Out-of-office BP is an important complement to traditional in-office BP, which remains the "gold standard" for screening, diagnosis, and treatment of hypertension. Many people believe that high blood pressure in the elderly is normal and not considered a disease, but in fact, the hypertension guidelines clearly state that the definition of hypertension applies to adults of any age over 18 years old, so the standard for hypertension in the elderly is also ≥140 mmHg and/or /90 mmHg, and that blood pressure levels above normal in the elderly, although common, are not normal and must be taken seriously and seen in a timely manner. It is important to pay attention to this situation and to seek timely medical attention and appropriate individualized treatment under the guidance of a physician.