After the invention of printing, it was periodical publications which revolutionized public communication more than anything else did. Classified according to place of publication, the annotated bibliography includes periodicals published in the German-speaking world. The aim of the handbooks, all of which were created based on critical assessments, is to make a reliable catalogue of all types of periodicals available to researchers in all historical disciplines. In addition to the bibliographies, the handbooks provide biographical data on editors, publishers and printers of periodicals as well as on other persons and institutions.