Media histories are valuable in an age when an increasingly high percentage of our lives are mediated through new and constantly evolving technologies. By conducting such excavations one can see the influences that guide technologies’ inception, growth, and decline as they facilitate societal changes. Typically, media histories are performed through the recovery and analysis of various documents providing support for a particular occurrence or argumentative position. Though seemingly objective, these evidentiary artifacts are shaped by the same types of sociocultural, economic, and political influences as the technologies that produce them. Through tracing a media history of this neglected genre, Lisa Gitelman’s Paper Knowledge: Toward a Media History of Documents establishes documents as artifacts of epistemological import. Gitelman identifies documents via their utility, or what she calls the “know-show function.” She argues: “Documents help define and are mutually defined by the know-show function, since documenting is an epistemic practice” (p. 1). Four chapters, focusing on small-job printed blanks, typescript books, xerography, and the PDF respectively, comprise Gitelman’s account of notable milestones and ruptures in document history. This insightful book is situated within a media history landscape wherein we do not just delve into the pasts of major media like computers and televisions but also those of photocopies and receipts.