P.J. is a common abbreviation for the name "Peter James" or "Paul John," but it can also refer to various individuals or characters in popular culture. In many contexts, P.J. is used as a nickname, often representing a friendly or casual persona. In entertainment, P.J. may refer to characters in movies, television shows, or books. For example, P.J. Masks is a popular animated series featuring young superheroes. Additionally, P.J. can denote specific brands or products, such as P.J. Salvage, known for its comfortable sleepwear.