Generation and the authors of several of these reference books, considered their work "pretty official". However, they stop short of naming the books canon, leaving the debate open. Star Trek writer and co-producer Ronald D. Moore dismisses such official material as "speculation", and says that the writing staff did not consider it canon. However, in a series of posts to the official Star Trek website's forums, Viacom Senior Director Harry Lang left no doubt that he considers the reference books as canon. Other publications Star Trek comic books and magazines are generally not considered part of the canon. Regarding IDW Publishing's comic book tie-ins to the 2009 film and its sequel, screenwriter Roberto Orci felt that the background information conveyed in those books could be considered canonically accurate. Using rules similar to the ones that governed Star Wars canon at the time, he acknowledged that the extended universe material he oversees could remain part of the accepted canon unless contradicted by future films or television series. Other material Nothing that takes place in Star Trek games, the Star Trek: The Experience attraction, Star Trek fan productions or Trekdom is considered part of the canon. Roddenberry-approved material Based on the amount of creative control Roddenberry exerted over the first seasons of Star Trek, some people argue that only Roddenberry-approved material should be considered canonical. Such an approach would eliminate from the canon anything Roddenberry disliked, as well as everything made after his death, including seven movies and multiple television series. However, Roddenberry himself preemptively rebuked such an attitude. He had hoped that Star Trek would go on after his death. As Star Trek was constantly improved by each following generation, he expected people to look back upon its humble beginnings as just that, the simple beginnings of something much bigger and better. Klingon language The Klingon language was first conceived by James Doohan for the movie Star Trek: The Motion Picture, and consisted only of a few words. Later, Marc Okrand proceeded to flesh out the sparse vocabulary into a real language, complete with grammar rules and phonology, and went so far as to publish The Klingon Dictionary (1985, revised edition 1992); the Klingon Language Institute was created soon thereafter. Okrand's Klingon language was used to write the Klingon dialogues heard in several Star Trek movies and episodes. Okrand has developed the language in an important way in two audio-courses: Conversational