There is no good or bad blood type because blood types are not like tumors, where there is a difference between malignant and benign tumors. Blood type is an artificial classification made by people according to whether the red blood cell membrane contains a certain substance or not. According to the classification, those containing A antigen are called A blood type, those containing B antigen are called B blood type, those containing both A and B antigen are AB blood type, and those containing neither A nor B antigen are O blood type. Therefore, blood type is only a classification method to distinguish red blood cells, there is no good or bad. If we really want to find out the benefits of AB blood type, it is that AB blood type can be transfused with any other blood type in small amounts in emergency situations, which used to be called universal recipient, and can only be implemented as a last resort. So, the benefit of AB blood type is that it can transfuse small amounts of blood of other blood types in emergency situations.