What is a stroke? what are the causes of strokes and what are the signs?

Most : Most strokes are caused either by blockage or rupture of a blood vessel in the brain. About three quarters of strokes occur when a blood clot closes a blood vessel in the brain; most of the remainder is due to a blood vessel bursting and bleeding into the brain. Major risk factors for stroke include atherosclerosis (hardening of the arteries), atrial fibrillation (a heart rhythm disorder), hypertension, high cholesterol, diabetes, and smoking. Family history of stroke also increases risk. Signs of stroke vary. Common signs are sudden paralysis in one part of the body, such as an arm or leg, drooping of one side of the face, slurred speech, or difficulty speaking. Headache and vertigo can be signs of stroke, but are much less common. Sudden onset of "the worst headache of my life" is very worrisome for a ruptured blood vessel in the brain. If stroke symptoms occur, it's critical to take action quickly. Stroke symptoms should be treated as a "brain attack", just as urgently as chest pain would be. Call 911 or go to the closest emergency room without delay.

CVA: Stroke is blockage of blood vessels causing secondary death of brain tissue. This can occur due to local thrombosis or distal embolism. The latter might be due to a clot from the heart, the former associated with hypertension, diabetes, high blood fats, homocysteine. Could present with sudden focal weakness of arm and leg, loss of speech or vision, gait imbalance, etc.