Superman is universally portrayed as a heroic figure in official DC publications, as is befitting of his status as both their original superhero and also one of their three mascots (the others being Batman and Wonder Woman). However he is not without his moments and a website known as Superdickery has latched onto Superman's more iconic "jerk" moments and heavily altered him into a completely unsympathetic monster by clever use of old comic book covers and strips that show Superman acting in very cruel or unusual manners (made all the more hilarious by the fact that the comics in question are official DC publications).
Superman is shown committing all manner of crimes and misdeeds in Superdickery and the authors intent is to show the Man of Steel as an utter sociopath - the famous quote from the website is "Superman Is A Dick".
The origins of the Superman portrayed in Superdickery is largely due to a trend in the Golden and Silver Ages of comics in which the publisher would show Superman doing something completely out of character - usually to draw audiences in and hopefully make them more inclined to buy the comic, if for no other reason than to sate their curiosity.
Of course to modern viewers such scenes are not only bizarre but if one has not read the story and/or knows nothing about Superman then they are inclined to think that Superman is nothing short of a monster - which Superdickery takes delight in parodying.
A link to the original website: Superdickery