Festivus was conceived by writer Dan O'Keefe and was celebrated by his family as early as 1966. The holiday was later introduced into popular culture by O'Keefe's screenwriter son Daniel on an episode of Seinfeld. The holiday's celebration, as it was shown on Seinfeld, included an unadorned aluminum "Festivus pole", practices such as the "Airing of Grievances" and "Feats of Strength", and the labeling of easily explainable events as "Festivus miracles".