Bizarro is a comic book character, he's basically a clone, completly "oposite" to the original Superman. This means it talks like a retard, since he'way of speaking is "backwards"-like, for instance, instead of "Hello" he says "goodbye" meaning "hello" and viceversa. Yeah...i know, he also has the oposite powers to supes, he has unlike Kent's laser vision he has freezing vision and unlike superman's freeze breath he has fire breath (yeah...). Here's the wikipedia version of what i just wrote:

[i]Bizarro is a fictional character, a doppelgänger of DC Comics’ Superman. Created by writer Otto Binder and artist George Papp, he first appeared in Superboy #68 (October 1958).

Due to a somewhat disjointed continuity, several versions of Bizarro have appeared in DC comic books, all of them inversions of Superman with gray or chalk-white skin, a twisted sense of logic which typically manifests as a superficial "opposite" of anything Superman would do or say and a resultant speech pattern ("Me am going to kill you" would mean "I will save you" in Bizarro speech). Due to his imperfections, Bizarro is frequently a foe of Superman, but sometimes finds himself in the role of hero (in this case, an anti-hero).
It has been suggested by both comic book fans and anthropologists that the Bizarro character, who is the opposite of Superman and all he stands for, was a metaphor for the Soviet Union at a time when Superman was seen as the embodiment of the United States in the 1950s.[/i]

Now i've posted these because, apparently a new animated movie on Superman is comming out, that has Bizarro as one of the main villains, a new arc in the superman continuity is going to be released featuring Bizarro, and the latest episode of Smallville shows Bizarro at the end of the season (as a main antagonist for that episode's finale)CLICK HERE TO SEE THE APPEARANCE OF BIZARRO IN SMALLVILLE
Bizarro has been used in comedy shows a lot too, mainly in the Seinfield episode of the "BIZARRO WORLD"(when Elaine is in the apartment of the Bizarro Jerry we can see a little superman Bizarro figure by the door)and in the SEALAB 2021 "BIZARRO"episode.
And their bizarro planet is square...yeah.