Hearts are muscular organs found in many animals, including humans. They are responsible for pumping blood throughout the body, supplying oxygen and nutrients to tissues while removing waste products. The human heart has four chambers: two atria and two ventricles, which work together to circulate blood. In addition to their biological function, hearts are often used as symbols of love and affection in various cultures. The heart shape is commonly associated with emotions and is frequently seen in art, literature, and celebrations like Valentine's Day. This symbolic representation highlights the heart's connection to feelings and relationships.