A professional wrestling feud is a staged disagreement between two wrestlers or factions of wrestlers over a purported slight or insult. It becomes part of the storyline that is ongoing, in televised matches in particular. Feuds may be protracted and last for months or even years or be resolved with implausible speed, perhaps during the course of a single long match. Feuds are often the result of the friction that is created between faces (the heroic figures) and heels (the malevolent, 'evil' participants). Some of the more popular feuds with audiences involve pitting former allies, particularly tag team partners, against each other. Depending on how popular and entertaining the feud may be, it is usually common practice for a feud to continue on for weeks, usually heading into a match in a Pay Per View.
Previously in the world of professional wrestling, many promoters wanted to "protect the business" and thus would further convince the live audience that the feuding wrestlers really did hate each other and looked to outdo each other. However, throughout the years, the wrestling business has become very open, which allowed the fans to see otherwise. A notorious incident involving the The Clique occurred during a World Wrestling Federation (WWF) House Show, in which the face pair of Shawn Michaels and Scott Hall embraced the heel pair of Kevin Nash and Triple H, thus "breaking" this illusion.
While many feuds in professional wrestling are staged for entertainment value, there have been successful feuds that actually originated from a real life rivalry and/or complete real life dislike of each other. A prime example of this was the feud between Bret Hart and Shawn Michaels, who despite having one of the WWF's and professional wrestling's most memorable on screen feuds, they really did have a total disdain for each other, based on many real life backstage feuds between the two. The on-screen feuds of Matt Hardy and Edge and later, Mick Foley and Ric Flair both stemmed from legitimate dislike for each other.