Clots are solid masses formed from blood components, primarily platelets and fibrin, that help stop bleeding when a blood vessel is injured. This process, known as coagulation, is essential for healing wounds and preventing excessive blood loss. However, clots can also pose health risks if they form inappropriately within blood vessels, leading to conditions like deep vein thrombosis or pulmonary embolism. These situations can restrict blood flow and may result in serious complications, making it important to understand how clots function in the body.