A hair straightener is a styling tool used to make hair smooth, straight, and sleek. It works by using heated plates to temporarily alter the shape of hair strands. Most straighteners have adjustable temperature settings for different hair types. Ceramic, titanium, and tourmaline are common materials used in the plates. Straighteners can also reduce frizz and add shine when used properly. They are popular for creating various hairstyles, from pin-straight looks to soft waves. Using a heat protectant is important to prevent hair damage. Compact and easy to use, they are a favorite in both salons and homes. Regular use requires proper care to maintain healthy hair.