A blood bank is a facility that collects, tests, processes, and stores blood and its components for transfusions. It plays a crucial role in healthcare by ensuring that safe and compatible blood is available for patients in need, such as those undergoing surgery or suffering from trauma. Blood banks work closely with organizations like the American Red Cross to organize blood drives and maintain an adequate supply. They also perform rigorous testing to screen for infectious diseases, ensuring that donated blood is safe for recipients. This process helps save lives and supports medical treatments across various healthcare settings.