Superman was created by writers Joe Shuster and Jerry Siegel in 1938 and made his first ever appearance in Action Comics #1. Supergirl arrived much later, created by writer Otto Binder and artist Al Plastino for Action Comics #252 back in 1959.
Originally Supergirl, whose real name is Kara Zor-El, has been written as the biological cousin of Superman. Later when comic writers wanted to establish Superman as the Last Son of Krypton her origins were muddied a bit, with a wide variety of characters using the Supergirl alias.
Superman has always been written as an orphan who escaped the death of the planet Krypton as a baby, only to be raised by humans here on planet Earth. Supergirl’s origins are far less straightforward and have been changed repeatedly over her life in fiction. In her most basic form though, she was a teenager when Krypton exploded and came to Earth as someone raised not as a human or an American, but as a Kryptonian.
While Superman has been an off and on fixture at the movies for decades, Supergirl faded from memory after that one awkward movie outing back in 1984. The character found new life in 2004 with a reintroduction in pivotal DC Comics storylines. More recently, Supergirl has found a home on television where The CW has reliably renewed the Supergirl TV series season after season.
But when it comes to Superman (aka Clark Kent) and Supergirl (aka Kara Zor-El), what you’re probably wondering is: What’s the difference? Besides their gender, that is.
The two Kryptonian characters have been intertwined since Supergirl’s introduction. Yet while their similar names and backgrounds might lead you to believe them identical, they actually have some big differences in their super-powered abilities.
Basic Power Sets
Both Superman and Supergirl have the same basic power sets. Both characters can fly, are invulnerable, have super-strength, super speed, super hearing, super vision, have heat-vision, and super strong cold-breath. But where Superman grew up on Earth and grew into his powers, Kara did not. Supergirl is newer to this whole super hero thing and lacks the experience Clark has at using his powers. That leaves her struggling to defeat villains that her cousin Superman could have taken down easily.
Both Superman and Supergirl (at least in their current incarnations… there have been others) are Kryptonians. Like all kryptonians they draw their strength from Earth’s red sun. Superman has spent far more time on earth than Supergirl, so he has absorbed more energy from our sun. That means Superman is far stronger than his female counterpart.
Eventually after spending time on Earth, Kara Zor-El manifested new powers never developed by Clark Kent. The Supergirl mythos explains these as a result of the natural difference between male and female Kryptonian bodies. Basically, Supergirl processes energy from our red sun differently than Superman’s does. These other powers take different forms but specifically Supergirl has been known to manifest protective crystals in times of stress as a form of protection.
Recent comic book Supergirl storylines have her gaining a power ring from the Red Lantern. This ring gives her powers similar to those of the Green Lantern, only where the Green Lantern’s ring is powered by force of will, Supergirl’s red ring is powered entirely by rage.
Given their origins, Supergirl and Superman will always be connected, but over the years DC’s writers have taken them on different paths. Whether it’s on television or movies or in print, each will fly to their separate destiny and separate success.