Possibly one of the greatest cartoons of the early 90s. Ren and Stimpy was created by John Kricfalusi and was picked up by Nickelodeon in 1991. The show is about a crazy, deranged asthma hound chihuahua (Ren) and a bumbling, idiot cat (Stimpy). It was known for its gross out humor and dirty jokes. However after years of censoring the hell out of the cartoons, John K was fired from Nickelodeon in 1993. Bob Camp, one of the writers on the original episodes and John K's close personal friend took over and Billy West (who voices Stimpy) took over the voice of Ren (who was orignally voiced by John K). These episodes were slightly toned down but you'll still see some dirty jokes. In 1996, after a 5 year run, the show was cancelled. 7 years later a new, "adult" version of the show aired on TNN (now known as Spike TV) in which their are more references to Ren and Stimpy's homosexuality (which was a common asked question when the show started). Then THAT got cancelled in 2004.
Ren and Stimpy was a great show and shows like Family Guy, South Park (both shows that John K absolutely LOATHE) and Beavis and Butthead have them to thank.
Ren and Stimpy spawned many catchphases (YOU EEDIOT! Happy happy joy joy, etc.)