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 ...

Last week’s season finale of The Knick saw the cocaine-addicted Dr. John Thackery try to solve the mystery of blood types before another doctor could do it. I won’t spoil what happened for you here, ...