The word Cordata is formed from the Latin word chorda meaning chord or notocord and ata meaning to bear. Organisms that have rodlike and elastic notochords and hollow nerve cords throughout life or at any stage of life are called chordata. Chordates make up about 3-5% of the world’s population. The number of non-cordata is 68,500 (Hiclman, 2008). Scientist Balfour (1880) created the order Chordata with animals having notochords. Bateson first named the episode.