A diffuser is a device designed to disperse essential oils or fragrances into the air, creating a pleasant and aromatic environment. Typically used in aromatherapy or for ambiance, diffusers come in various types, including ultrasonic, nebulizing, heat, and evaporative. Ultrasonic diffusers use water and ultrasonic vibrations to break down essential oils into fine particles, releasing them as a mist into the air. Nebulizing diffusers disperse oils without water, using pressurized air to atomize the oil into tiny droplets. Heat diffusers, like candle or electric diffusers, use heat to evaporate oils, while evaporative diffusers utilize a fan to blow air through a pad soaked with essential oils. Each type offers unique benefits and methods of dispersing fragrances effectively.