Blood type is a specific classification of your blood based on the presence or absence of certain antigens on the surface of your red blood cells. Antigens are molecules that stimulate an immune response.
Your blood type dictates your ability to donate and receive blood for life-saving blood transfusions. Antigens trigger the body’s immune response to anything foreign, so safe blood transfusions require the correct matching or cross-matching of compatible donor and recipient blood types.
Globally, type O+ is the most common and type AB- is the rarest.
Blood type & Percent (%) of global population