Supergirl is one of the fictitious characters in the DC comic's universe who is considered to be the female equivalent of Superman. She made her debut appearance in the Superman #123 (1958) and is the brainstorm of writer Otto Binder and artist Al Plastino. Due to the irregularity of the depiction of Supergirl, she has evolved over the years.

The first adaptation of Supergirl is of Kara Zor-El the sole survivor after her home place, Argo City (a city of planet Krypton) was destroyed. She was sent to Earth in a small rocketship by her scientist father Zor-El to be looked after by her cousin Kal-El, known to everyone as Superman. Her parents sent her with a costume that closely resembled that of Superman so that she would be eventually recognized by Superman. She was 15 when she first landed on earth and she assumed the secret identity of Linda Lee an orphan from Midvale Orphanage. She buried her blond hair under a brunette wig and was eventually adopted by Fred and Edna Danvers. Her secret double life is known only to Superman, her foster parents and later the league of Super-Heroes. She has the same Kryptonian super powers and is defenseless against Kryptonite. Supergirl Kara eventually dies in the 'Crisis of Infinite Earths' and makes way for the second version of Supergirl.

The second supergirl debuted in Superman #16 (1988) and was artificially created by Lex Luthor from his wife's protoplasm matrix after she was killed. She had powers like flight, shape-shifting, invisibility and telekinesis. The third Supergirl has some human origins. During the crisis, Supergirl Kara merged her protoplasmic form with a human girl Linda Danvers spirit and embodiment and Supergirl gets reincarnated. The popularity of the comic, led to a feature film Supergirl in 1984 starring Helen Slater as Supergirl. It has also been made into an animated series.