Android 17 was created for destorying Son Goku. He is not totally machine like 16. He is part human too he also he unlimited power so he will never run out of power. He has a sister Android 18. They make an appearance in the Trunks Speical and the Cell saga. No one know what happens to him after the cell saga. He also makes an appearance in the GT as Super 17 but later on get's destoryed by SSJ4 Goku.
