Android 16 was created by Dr. Gero along with #18 and #17. he was the first to be made. But something was differnt about him he was not really into fighting and was more peaceful. Although he helped fight against the Z Warriors he didnt like to fight. He wasnt very popular with the others androids.
Later on he gets injured by fighting Cell in his first form. He then sits out for the rest of the series he then turns good. when Cell was hunting #18 for completion he tried to assure her it was going to be ok. He even protected her when Cell found her. He later gets killed by Cell when Gohan was fighting Cell.