A stroke is a sudden interruption in the blood supply of the brain. Most strokes are caused by an abrupt blockage of arteries leading to the brain (ischemic stroke).  Other strokes are caused by bleeding into brain tissue when a blood vessel bursts (hemorrhagic stroke).

The acronym FAST (Facial drooping, Arm weakness, Speech difficulties and Time) has been used by the National Stroke Association, American Heart Association and others to educate the public on detecting symptoms of a stroke.

Information located: http://www.strokecenter.org/patients/about-stroke/what-is-a-stroke/