what blood types are there
There are 8 different blood types (A+, A-, B+, B-, O+, O-, AB+, AB-). The most well known and medically important blood types are in the ABO group. Even though type AB is the rarest blood type, type AB plasma can help people with any blood type. 2  So, more type AB plasma donors are always needed. 3  By giving plasma regularly you can help people with AB, O, B and A blood types.