A hair flat iron, also known as a hair straightener, is a styling tool used to straighten or smooth out hair. It typically consists of two heated plates, usually made of ceramic, titanium, or tourmaline, that clamp together to press the hair between them. The heat from the plates helps break down the hydrogen bonds in the hair, making it easier to straighten or create sleek, smooth styles. Some flat irons also have adjustable temperature settings to suit different hair types, from fine to coarse. In addition to straightening, flat irons can be used for creating curls, waves, or flips, depending on the technique used.