You'll find 4 blood sorts: A, B, AB, or O. Also, blood is both Rh-constructive or Rh-negative. So When you have kind A blood, it's possibly A beneficial or A destructive. Which kind you might be is essential if you want a blood transfusion. Along with your Rh issue https://www.youtube.com/watch?v=buIHtQY7fCU