Hair Care & Cutting
Hair services are the core of most salon work, and sound cutting and care begin with understanding the structure and growth of hair. This chapter covers the layers of the hair, the hair growth cycle, and the fundamental cutting concepts of elevation, angle, and line that create shape.
Structure of the Hair
A hair strand (shaft) has three layers. The cuticle is the tough, translucent outer layer of overlapping scales that protects the interior; healthy, closed cuticles give hair shine. The cortex is the thick middle layer that holds the hair's natural pigment (melanin) and the disulfide and other bonds responsible for strength, elasticity, and how the hair responds to color and perms. The medulla is the soft central core, often absent in fine hair. The root sits below the skin in the follicle, nourished by the papilla.
The Hair Growth Cycle
Hair grows in a repeating three-phase cycle. Anagen is the active growth phase and can last for years; most scalp hair is in anagen at any time. Catagen is a short transition phase in which growth stops and the follicle shrinks. Telogen is the resting phase, ending when the old hair sheds and a new anagen phase begins. Because hairs are at different points in the cycle, we shed some hair every day. Understanding this cycle helps you set realistic expectations for growth and shedding.
Cutting Fundamentals: Elevation, Angle, and Line
Haircut shape is built from a few controllable variables. Elevation (projection) is the angle at which a section is lifted from the head: 0 degrees produces blunt, one-length weight; 90 degrees builds uniform layers; 180 degrees creates long, graduated layers. The cutting line (horizontal, diagonal, or vertical) and consistent tension determine where weight is removed or kept. Matching technique to hair type matters — fine hair usually looks fuller with blunt lines and controlled layering rather than heavy thinning, which can make sparse hair look thinner.