A magalog is a promotional copy of a magazine

Magazine

Magazines, periodicals, glossies or serials are publications, generally published on a regular schedule, containing a variety of articles. They are generally financed by advertising, by a purchase price, by pre-paid magazine subscriptions, or all three...

, usually in a 12-page catalog format. The name is a portmanteau of "magazine" and "catalog". Magalogs help introduce magazines to new readers. It can also help existing readers see new or upcoming changes, additions, or improvements to the magazine. An alternate use can include catalogs that are presented with content, not just advertising

Advertising

Advertising is a form of communication used to persuade an audience to take some action with respect to products, ideas, or services. Most commonly, the desired result is to drive consumer behavior with respect to a commercial offering, although political and ideological advertising is also common...

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