"Helio" is a prefix derived from the Greek word "helios," meaning "sun." It is often used in scientific terms related to the sun, such as heliocentric, which describes a model of the solar system where the sun is at the center. The term can also refer to heliotherapy, a treatment that uses sunlight for healing purposes. In astronomy, "helio" can relate to the study of solar phenomena, including solar flares and sunspots. Additionally, it is used in the context of helium, a chemical element that is a byproduct of nuclear fusion in the sun. Understanding "helio" helps in exploring various solar-related concepts.