Schadenfreude is a term used to describe pleasure taken from other people's pain. It is a feeling that we all have experienced, me especially, when celebrities have highly publicized break-ups, and in children's cartoons when one of the characters is involved in a dynamite explosion or trips on a banana peel.
According to the article, "Malicious Pleasure: Schadenfreude at the Suffering of Another Group ," "John Heider (1958) argued that schadenfreude is malicious because pleasure is a "discordant" reaction to another's misfortune. Unlike the "concordant" reaction of sympathy, schadenfreude establishes an antagonistic relationship to the unfortunate other. For this reason Heider saw schadenfreude as harmful to social relations." In other words, where we should feel sympathy for other people when they suffer, we instead feel glee and happiness.
One of the hypotheses for the cause of schadenfreude is that of perceived identity and inferiority. An experiment conducted in 1996 by RH Smith et al included a male subject who was portrayed as being much superior/inferior to an experimental group. The male subject then suffered the misfortune of being denied admission into medical school. The group who perceived themselves inferior felt more pleasure at his suffering. The study suggested that feeling inferior to the successful peer is what led to schadenfreude in response to the adversity.
When people feel threatened by another group, schadenfreude tends to increase in between groups. An example of this is apparent in the world of sport. One researcher studied German and Dutch football fans. The threat of the Netherlands's chronic inferiority in football increased Dutch schadenfreude toward Germany's loss in the world cup. To make it more relevant to us, Packers and Viking fans experience joy when the other team makes a fumble or suffers a penalty.