Intertextuality is defined as the relationship between texts, especially literary ones, where one text shapes the meaning of another. There are three types of intertextual relationships: obligatory, where the writer deliberately invokes comparisons between texts; optional, where the writer pays homage to original works or rewards those who are familiar with source texts; and accidental, which is undefined. Obligatory intertextuality is exemplified by 2Pac's "California Love" music video borrowing imagery from the Mad Max films. Optional intertextuality can involve acknowledging similarities between works, like director J.J. Abrams doing so between Star Wars: The Force Awakens and the original Star Wars film.