A curling iron is a heated styling tool used to create curls or waves in hair by wrapping sections around a cylindrical barrel that distributes consistent heat. Typically made with materials like ceramic, tourmaline, or titanium for even heat and reduced damage, it comes in various barrel sizes to achieve different curl types—from tight ringlets to loose beach waves. Most curling irons feature adjustable temperature settings, a clamp or clip to hold hair in place, and a cool tip for safe handling, making them a versatile and essential tool for both everyday styling and more polished looks.