Lifeform

The following outline is provided as an overview of and topical guide to life forms: A life form (also spelled life-form or lifeform) is an entity that is living, such as plants (flora), animals (fauna), and fungi (funga). It is estimated that more than 99% of all species that ever existed on Earth, amounting to over five billion species, are extinct. Earth is the only celestial body known to harbor life forms. No form of extraterrestrial life has yet been discovered.