Heart valves are essential structures in the heart that control blood flow between its chambers. There are four main valves: the tricuspid valve, pulmonary valve, mitral valve, and aortic valve. These valves open and close in response to pressure changes, ensuring that blood moves in the correct direction and preventing backflow. Each valve consists of flaps called leaflets that work together to regulate blood flow. The tricuspid and mitral valves are located between the heart's upper and lower chambers, while the pulmonary and aortic valves are found at the exits of the heart. Proper functioning of these valves is crucial for maintaining efficient circulation.