When a person voluntarily has blood drawn and used for transfusions or made into biopharmaceutical medications then the Blood donation happens. this process is called fractional . Blood banks participate in the collection process and also procedures that follow it. Mostly some of the blood donors are unpaid volunteers who donate blood for a community supply.  some countries  establishment of  their supplies are very limited and also donors usually give blood when family or friends need a transfusion .Many donors donate as an act of charity, but in  some countries that allow paid donation , in some cases there are incentives other than money such as paid time off from work. some People also have blood drawn for their own future use. Donating blood in many cases is relatively safe, but some donors have bruising where the needle is inserted or may feel faint. some of the Potential donors are evaluated for anything that their blood unsafe to use.  screening included testing for diseases that can be transmitted by a blood transfusion, and also HIV and viral hepatitis.