SSI’s acclaimed D.U.M.I.E.S. series — which stands for dealers, users, managers, installers, engineers and salespeople — has been a favorite among readers. The series was designed to educate readers about advances in technology and systems that are likely to shape this decade’s progression of video surveillance and access control. In this gallery, look back at some of the illustrations, dating back to 2004, featured for each topic in the series.