Trivia: Director Tommy Wiseau shot the film using a dual camera-rig. He shot the film on both a 35mm film camera and an (at the time) new HD movie-camera, both mounted to the same rig so they could more-or-less get similar angles, as he didn't quite understand the differences in the mediums and wanted to experiment shooting the film with both simultaneously.
Trivia: Greg Sestero is called Mark as a misguided reference to the actor Matt Damon and his film "The Talented Mr. Ripley." Writer/Director Tommy Wiseau was very taken with the film, and decided to name a character after Damon... however, he misheard "Matt Damon" as "Mark Damon" once during a conversation, and thus wrote the name "Mark" into his script for "The Room" instead of the proper "Matt." He never bothered to change the name to "Matt", thus making his intended reference null-and-void.
Trivia: The character who catches Lisa and Mark's cheating during the party at the climax was meant to be Peter the psychologist character from earlier. However, the actor became unavailable (with some theorizing he simply refused to return to set after filming his initial few scenes), and his dialog was instead given to this new character.
Trivia: Co-Star Greg Sestero subsequently wrote a tell-all book about director Tommy Wiseau and the making of the film titled "The Disaster Artist." The book confirms that the film is indeed intended to be a serious drama that simply failed spectacularly, despite some fan-theories suggesting it was "purposely badly made." "The Disaster Artist" has subsequently been optioned for a film adaptation.
Trivia: The film has gained great cult status as a "so bad, it's good" film. Director Tommy Wiseau, who originally intended the film to be a serious drama, subsequently began to market the film as farcical black comedy in order to capitalize on the fact audiences found it funny rather than dramatic as he had originally intended. (And many have theorized he also began to market it as a comedy to help his bruised ego over the failure of the film as a drama).
Trivia: A common misconception is that the film is titled "The Room" due to the fact that it originally was conceived as a stage-play taking place in a single-room, and that the title was simply not changed once it became a film with multiple locations. Director Tommy Wiseau has stated that this fan-theory is false, instead giving a (somewhat nonsensical) explanation that the title "The Room" was inspired by the fact that he tried to think of a "place" where people are safe to have experiences both good and bad. He also emphasizes that it's important that he titled the film "THE Room" instead of "A Room." To this day, fans are still debating on what Wiseau means by his explanation of the title.