Hair serum is a lightweight, liquid product designed to enhance the appearance and health of hair. It typically contains a blend of silicones, oils, and other nourishing ingredients that help to smooth frizz, add shine, and protect against damage. Hair serums can be used on various hair types and are often applied to damp or dry hair for best results. Using hair serum can also provide additional benefits, such as heat protection when styling with tools like hair dryers or straighteners. Regular application can lead to softer, more manageable hair, making it a popular choice for those looking to improve their hair care routine.