A habitable zone is an area around a star where it is comfortable enough for living things like plants and animals to exist. It's like living in the Goldilocks zone- not too hot, not too cold, but just right. In order for it to be habitable, the zone needs to be the right distance away from the star. If it is too close, the heat will be too hot and everything will burn up, and if it is too far away it will be too cold and everything will freeze. When the zone is just right, the temperature is perfect and things can live!