What tool is commonly used to create curls in hair?

The tool that is most commonly used to create curls in hair is the curling iron. This specialized styling tool is designed with a heated barrel that curls the hair strands around it when wrapped. By holding the hair on the barrel for a few moments, heat is applied, allowing the hair to take shape and form beautiful, defined curls.

In contrast, a blow dryer is used primarily for drying hair and can enhance volume, but it does not create curls on its own. Similarly, a flat iron is designed to straighten hair and can sometimes create waves or curls when used in a specific manner, but it is not its primary function. A hair straightener also focuses on smoothing the hair, which is the opposite of curling. Therefore, the curling iron is the dedicated tool that effectively achieves the desired curly hairstyle.