Medically reviewed by Amelia MacIntyre, DO There are different blood types: A, B, AB, and O, with each also being Rh-positive or Rh-negative.Knowing your blood type is important for safe blood ...

Blood types are a classification of blood based on the antigens present in red blood cells. In the United States, O-positive is the most common blood type, and AB-negative is the rarest. A blood ...

Red blood cells are complex — there's much more to blood types than A, B and O. When you purchase through links on our site, we may earn an affiliate commission. Here’s how it works. Many people know ...

Dr. Karl Landsteiner won the Nobel prize in 1930 for developing the ABO blood group system. The ABO system is the best known method of classifying blood types. It’s important to know your blood type ...