Which hair color technique uses foils to isolate sections of hair?

The technique that uses foils to isolate sections of hair is known as highlights. Highlights involve lightening specific strands of hair, and the use of foils helps to separate the lightened hair from the other hair, allowing for a more controlled and precise application of the hair lightener. The foils help to keep the lightener from over-processing the surrounding hair, resulting in a more defined separation of colors. This method allows the stylist to create depth, dimension, and a sun-kissed effect by varying the placement and thickness of the foils.

In contrast, balayage is a technique where color is painted onto the hair for a more natural, blended look without the use of foils. Ombre refers to a more dramatic color gradient where hair gradually transitions from dark to light, typically from the roots to the ends, but does not necessarily use foils. Color melt involves blending different shades of color together seamlessly, often without isolation methods like foils, focusing instead on a smooth transition of colors throughout the hair. Thus, the distinct use of foils is what clearly identifies highlights among these other techniques.