A trade journal is a publication written for people who work in a specific trade or industry. Trade journals provide current industry news and articles about new products and trends, including regulatory developments which may affect an industry. Advertising and industry related job notices also appear in many trade publications.
If you are starting a business it's a good idea to read trade journals relating to the industry in which you will be operating. There are several ways to find trade journals for your industry :
Many trade journals are now published on the Internet; some provide free access while others require a subscription or membership. Try a Google search using one word which describes your industry and include the word "magazine".
Business publications and industry trade journals have been collected by the New York Public Library for more than 100 years. Some early issues, pre-1923, of these journals have now been digitized and may be accessed through the Library's catalog and Hathi Trust.
See this six-part blog —parts 1 through 6—for links to a selection of historical digitized business publications and industry trade journals.