The most popular and enduring version of Supergirl is Kara Zor-El, Superman's cousin, who shares his super powers and vulnerability to Kryptonite.

Like her cousin, Kara was born on the planet Krypton.

In Action Comics #252 (May 1959), Superman places Kara in Midvale Orphanage under strict orders not to reveal her superpowers. She adopts the identity of Linda Lee and hides her blonde hair beneath a pig-tailed, brunette wig.

Like Superboy before her, Supergirl joins the Legion of Super-Heroes. She would leave at age 21 (the normal age limit for members is 18).

Supergirl was created by writer Otto Binder and artist Al Plastino in 1959. She first appeared in Action Comics and later branched out into animation, film, and television.

Due to changing editorial policy at DC, Supergirl was initially killed off in the 1985 limited series Crisis on Infinite Earths. DC Comics subsequently rebooted the continuity of the DC Comics Universe, re-establishing Superman's character as the sole survivor of Krypton's destruction.

In Superman Family #208 (July 1981), Kara quits her job as a student advisor and moves to New York City to become an actress in the TV soap Secret Hearts.

In Action Comics #318 (Nov 1964), Kara graduates from Midvale High School, winning a four-year scholarship to Stanhope College where she joins the Alpha Lambda sorority.

In Action Comics #270 (November 1960) Superman entrusts Kara with the knowledge of Batman and Robin's true names.

Laura Vandervoort played Kara in 23 episodes of Smallville (2001-2011). She would later play the role of Indigo in the 2016 Supergirl TV series starring Melissa Benoist.