Clotting factors are proteins in the blood that help control bleeding. When a blood vessel is injured, these factors work together in a complex process called the coagulation cascade. This process leads to the formation of a blood clot, which seals the wound and prevents excessive blood loss. There are several clotting factors, each identified by a Roman numeral, such as Factor I (fibrinogen) and Factor VIII (antihemophilic factor). A deficiency or dysfunction in any of these factors can lead to bleeding disorders, such as hemophilia, where the blood does not clot properly.