This document provides an overview of strokes, including the different types, how they affect the brain, common signs and symptoms, risk factors, statistics, testing, and rehabilitation. A stroke occurs when blood flow to the brain is interrupted, depriving brain cells of oxygen. There are two main types - ischemic (caused by clots) and hemorrhagic (caused by bleeding). Timely treatment is critical to reduce damage. Risk factors include age, gender, family history, prior strokes, smoking, diet, activity level, weight, and medical conditions. Stroke is a leading cause of disability and the third leading cause of death in the United States.