What are the two main stages of perming?

The two main stages of perming are indeed waving solution application and neutralization.

During the waving solution application stage, the perm solution, which contains chemicals that break down the hair's protein structure, is applied to the hair. This allows the hair to be reshaped into a curl pattern when wrapped around rods or curlers. The waving solution penetrates the hair shaft, causing the hair to soften and take on the shape of the rods.

The second stage, neutralization, involves applying a neutralizer that re-establishes the hair’s protein structure in its new shape. The neutralizer works by closing the hair cuticles and setting the new curls or waves in place, ensuring the style lasts longer.

These two stages are crucial because they transform straight hair into curly or wavy hair effectively, demonstrating the chemical process fundamental to perming. Other mentioned options focus on different aspects of the hair styling process, such as preparation and finishing, but they do not encompass the core chemical processes involved in creating the permanent curl shape.