The process by which blood clots form is called coagulation. Coagulation is a complex physiological process that helps prevent excessive bleeding when blood vessels are injured. It involves a series of chemical reactions, leading to the transformation of the protein fibrinogen into fibrin, which forms a mesh that stabilizes the blood clot. Several factors, including platelets, clotting factors, and various signaling molecules, participate in this process, making it vital for maintaining hemostasis and proper healing after injuries.