There are four blood types in humans: A, B, AB, and O. An individual with blood type A has antibodies for B, so he or she can't receive type B blood. Similarly, a person with blood type B has antibodies for type A and can't receive type A blood. A person with AB blood type has no antibodies and can receive blood from anyone. A person with type O blood has both A and B antibodies and can receive blood only from someone else with type O blood. Based on this information, someone with type B blood can donate to
blood groups B and AB.
Someone who has blood type B can donate blood to those who don't have antibodies for B. These include other people with type B blood (they have antibodies for A only) and those with type AB blood (they don't have any antibodies).