We're a collaborative community website that anyone, including you, can build and expand concerning the shared universe created by the collective canon of the Psycho, The Texas Chainsaw Massacre, Halloween, Friday the 13th, Evil Dead, A Nightmare on Elm Street, and Child's Play franchises, as well as the standalone films Black Christmas and Behind the Mask: The Rise of Leslie Vernon.
BUT WAIT! You mask ask. How are all these franchises connected. This connection first began with the appearance of Freddy Krueger's infamous glove in Evil Dead II. This universe widened when the Necronomicon Ex-Mortis appeared in Jason Goes to Hell: The Final Friday, and Freddy Krueger's cameo in the same film, as well as being solidified by the crossover film Freddy vs. Jason.
The universe would continue to grow when Freddy's glove and Jason's hockey mask in an evidence locker in Bride of Chucky, thus tying in the Child's Play franchise. This evidence locker would also tie into the The Texas Chainsaw Massacre franchise via the presence of Leatherface's chainsaw, and the Halloween franchise with Michael Myers' mask being present.
The Psycho franchise would also be drawn into the fold via the theory that Sam Loomis from Psycho and Sam Loomis from Halloween are one and the same. The film Behind the Mask also exists in a world where many of the characters from the previous films exist as real people, and Eugene from Behind the Mask is intended to be one and the same as Billy from Black Christmas. Leslie Vernon is also mentioned in Hatchet II, bringing forth the Hatchet franchise.