In the popular imagination, archives are remote, largely obsolete institutions: either antiquated, inevitably dusty libraries or sinister repositories of personal secrets maintained by police states. Yet the archive is now a ubiquitous feature of digital life. Rather than being deleted, e-mails and other computer files are archived. Media software and cloud storage allow for the instantaneous cataloging and preservation of data, from music, photographs, and videos to personal information gathered by social media sites. In this digital landscape, the archival-oriented media theories of Wolfgang Ernst are particularly relevant. Digital Memory and the Archive, the first English-language collection of the German media theorist’s work, brings together essays that present Ernst’s controversial materialist approach to media theory and history. His insights are central to the emerging field of media archaeology, which uncovers the role of specific technologies and mechanisms, rather than content, in shaping contemporary culture and society. Ernst’s interrelated ideas on the archive, machine time and microtemporality, and the new regimes of memory offer a new perspective on both current digital culture and the infrastructure of media historical knowledge. For Ernst, different forms of media systems—from library catalogs to sound recordings—have influenced the content and understanding of the archive and other institutions of memory. At the same time, digital archiving has become a contested site that is highly resistant to curation, thus complicating the creation and preservation of cultural memory and history.