Stroke can present in various forms. Disease of Carotid arteries, that run along each side of neck, are mainly involved in the genesis of Stroke. These arteries supply blood from heart to the brain.

Stroke is clinically of three types:-

	TIA - Transient Ischemic Attack or Mini Stroke
	Evolving Stroke
	Completed Stroke

TIA - Transient Ischemic Attack or Mini Stroke - In this type of stroke Fatty palque is formed in the carotid arteries, and when it is sufficient enough to reduce critical amount of blood flow to the brain this type of transient ischemic attack occurs.

Symptoms of TIA are
sudden weakness or numbness of the face or a limb;
difficulty in speaking;
dimmed, blurred or double vision;
balance problems;
severe headache;
sudden changes in personality and mental ability.

The effects of TIA are usually brief, but cannot be ignored because they indicate the possibility of a full-blown stroke in the future, or a heart attack. About a third of those suffering from TIA will have a stroke, often within a year.
About 10 percent of strokes are preceded by TIAs.

Completed Stroke : This is an episode of focal cerebral dysfuction due to cerebral infaction or haemorrhage, with symptoms lasting for longer than 24 hrs. Stroke usually evolve rapidly over a few minutes, and reach maximum disability within an hour or two. Sometimes a slower course occurs. 
Headache is a common symptom of acute stroke. Vomiting  and epileptic seizure with depressed consciousness may also occur. 
The precise features of stroke depend upon the territory of the brain involved. 

Evolving Stroke : In some patients the symptoms develop in the matter of hours or days. This may be due to cerebral tumour or subdural hematoma or may be due to slow occlusion of major cerebral vessels.  

Cerebral Thrombosis : is caused by blood clot in one of the arteries in the brain. The clot may have travelled in the neck or the brain from other part of the body.

Hemorrhagic Stroke : involves a blood vessel in the brain which may have burst or leaked blood.

Both these types cause destruction of the crucial brain cells by depriving them of oxygen and sugar, which may take few minutes to hours.