Krypton (comics)
Krypton is a fictional planet in the DC Universe and the native world of Superman. In some stories, it is also the native world of Supergirl, Krypto the Superdog, and Power Girl. Krypton has been portrayed consistently as having been destroyed just after Superman's flight from the planet, with exact details of its destruction varying by time period, writers and franchise. Kryptonians were the dominant species of Krypton.
The planet was created by Jerry Siegel and Joe Shuster, and was first referred to in Action Comics #1 (June 1938). The planet was given its first full-fledged appearance in Superman #1 (Summer 1939).
Read more about Krypton (comics): Overview, Krypton's Revisions