Trade magazine
A trade magazine, also called a trade journal or professional magazine (and colloquially or disparagingly a trade rag), is a magazine whose target audience is people who work in a particular trade or industry. Its main goals are to keep members of the industry abreast of new developments (in which role it functions similarly to how academic journals, scientific journals, medical journals, and engineering journals serve their audiences) and to serve targeted advertising to them, which earns a profit for the publication and sales for the advertisers while also providing sales engineering–type advice to the readers, helping them with industrial purchasing and investment decisions. The collective term for this area of publishing is the trade press (although that term sometimes also refers to publishers of trade paperbacks).
Trade magazines typically contain advertising content centered on the industry in question with little if any general-audience advertising. They also generally contain industry-specific job notices, a highly pertinent aspect to many readers.