Trade publications are periodicals and they look like magazines. The are written for professionals in a a specific field, but they aren't peer reviewed and don't include scholarly journal articles. They publish articles about issues of interest to professionals in a field and may refer to the results of research published in scholarly journals of that field. Trade publications include advertisements for products of interest to the profession. The are also more likely to include letters to the editor or other content contributed by readers.
Some examples of trade publications are
An example is a publications information page from Academic OneFile for a trade publication called RV Business. The page indicates that full text for RV Business is available from October 7, 1991 through July 1, 2011. If RV Business is still in publication, Academic OneFile doesn't have permission from the publisher to make more current issues searchable or to provide the full text for any article more recent than July 1, 2011.