An oil burner is a device used to heat essential oils, or fragrance oils, releasing their aroma into the air. It typically consists of a small bowl or dish to hold the oil, placed above a candle or tea light that gently heats it from below. As the oil warms, it evaporates, spreading its scent throughout the room. Oil burners are often made from ceramic or metal and are used for aromatherapy, relaxation, or simply to freshen up a space.