http://en.wikipedia.org/wiki/Trade_journal

A trade journal is a periodical, magazine or publication printed with the intention of target marketing to a specific industry or type of trade/business. Trade journals typically contain heavy advertising content focused on the industry in question with little if any "general audience" advertising. They also generally contain industry-specific job notices. Many trade publications can also be considered newsmagazines with a very specific topical focus.

http://www.filmjournal.com/filmjournal/about_us/index.jsp

Film Journal International, now in its 73rd year, is a trade publication covering the motion picture industry, including theatrical exhibition, production, distribution, and allied activities.