Since 1968, more than 850 original novels, short story collections, episode and film novelizations, and omnibus editions have been published. The Star Trek franchise's first tie-in publications were James Blish's 1967 volume of episode novelizations and Mack Reynolds's 1968 young adult novel Mission to Horatius. For original audio books, in-universe references, picture books, photo comics, and fictional retrospectives, see List of Star Trek tie-in fiction. For Star Trek comics and graphic novels published by Marvel Comics, DC Comics, IDW Publishing, see Star Trek (comics).