Which technique uses heat to create curls in hair?

The technique that employs heat to create curls in hair is hot rollers. Hot rollers are heated tools that, when applied to sections of hair, enhance the natural curl pattern or create new curls entirely. As the rollers heat the hair, the heat is transferred to each strand, allowing the hair cuticle to soften. This enables the hair to mold into the shape of the roller. Once the rollers cool, the hair retains the curl, resulting in bouncy, defined curls or waves.

Using hot rollers provides a quick and effective way to achieve voluminous curls, making them a popular choice for styling. Other techniques, such as twists and finger waves, do not involve heat in the same way and rely more on the manipulation of the hair's structure and styling products to maintain their shape. Knotting is generally a method used to secure hair rather than to curl it.