This document discusses hypertension (high blood pressure), including its classification, causes, symptoms, diagnosis, and treatment. It defines the different stages of hypertension according to blood pressure readings. Lifestyle modifications are recommended initially, including diet changes and exercise. If lifestyle changes do not control blood pressure, medications such as diuretics, beta-blockers, calcium channel blockers, ACE inhibitors, and other drug classes may be used. The goal of treatment is to prevent complications in target organs like the heart, brain, and kidneys by maintaining a blood pressure below 140/90 mmHg.