Blood donation is Alka about gifting life to other people. As blood is an essential part of your body then every donor has to go through a physical test to prevent infections diseases through transfusions. An average donor is allowed to Dona about 1 pint of blood at once which is 1/10 of the quantity an adult holds in their body. To save three life’s one pint of blood is sufficient. Mainly 4 types of blood groups can be found A, B,AB, O. AB+ blood group is the universal recipient and O negative is the universal donor. The donation is a pain free process that runs for about 10-15 minutes. Doctors who Collect the blood use sterile equipment to ensure the safety.