Blood Bank is a facility that stores and preserves blood/blood components collected through donations for later use in transfusions. The first blood depot was established in Britain during WWI. Key developments include the first mobile blood bank in 1930s Spain, the first hospital blood bank in Chicago in 1937, and establishment of standards for blood collection/storage. Blood is separated into components like red blood cells and plasma, and stored short or long-term depending on the component. Online blood banks now facilitate donor/recipient matching. Donations are needed to address ongoing scarcity issues.