A blood donor is an individual who voluntarily gives their blood to be used for medical purposes. This blood can be transfused to patients in need, such as those undergoing surgery, cancer treatment, or trauma care. Blood donation is a crucial part of healthcare systems, as it helps save lives and supports various medical procedures. The process of donating blood is safe and typically takes about an hour. Donors are screened for health conditions and must meet specific criteria, such as being at least 17 years old and weighing a minimum of 110 pounds. Organizations like the American Red Cross facilitate blood donation drives and ensure that donated blood is tested and stored properly.