Hair growth is not a continuous process but rather occurs in cycles. Each hair follicle undergoes three phases: Anagen, Catagen, and Telogen. 1. Anagen (Growth Phase) The Anagen phase is the active growth period of hair follicles. Hair grows from the roots during this phase, which can last several years. In laser hair removal, the Anagen phase is the most crucial because the hair is connected to the follicle, allowing the laser energy to travel down the hair shaft and effectively destroy the follicle. 2. Catagen (Transition Phase) During the Catagen phase, the hair stops growing and detaches from the follicle. This phase is short, lasting about two to three weeks. Since the hair is no longer connected to the follicle, laser treatments are less effective during this phase. 3. Telogen (Resting Phase) The Telogen phase is the resting period before the hair falls out and is eventually replaced by a new hair. This phase can last for several months. Like the Catagen phase, laser hair removal treatments are less effective during Telogen because the new hair has not yet formed a connection to the follicle.