What is a common tool used for highlighting hair?

Foils are a common tool used for highlighting hair because they allow for precise application of lightener or color to selected sections of hair. By wrapping the sections of hair in foils, stylists can isolate them from the rest of the hair, which prevents the color or bleach from spreading to unwanted areas. This technique not only helps achieve a more refined and controlled highlight but also aids in the processing of the color by trapping heat, which can enhance the effectiveness of the lightening process.

While brushes and combs are important tools for overall styling and sectioning, they do not provide the same level of precision in highlighting as foils do. Rollers are primarily used for creating curls or waves rather than for highlighting techniques. Therefore, using foils is the preferred method in professional hair highlighting.