Chickenpox is a highly contagious viral exanthem caused by the varicella-zoster virus. It is characterized by the development of an itchy rash consisting of fluid-filled blisters that appear in various stages of development across the body. The illness is typically self-limiting, meaning it resolves on its own, but it can present complications, especially in high-risk or immunocompromised populations. Because of its high transmissibility, prevention strategies, including the use of vaccinations, are standard public health measures designed to minimize community spread and achieve herd immunity.