Digitalization disrupts business models and smartifies products and services. Based on the ever-faster emergence and adoption of digital technologies such as the Internet of Things, blockchain, or augmented reality, digitalization irreversibly changes our private lives and organizational routines from all industries on a global scale. Thereby, digitalization develops unlimited potential in terms of innovation, connectivity, efficiency and productivity improvements. However, research and practice still lack a fundamental understanding of the nature of digital technologies. To address this gap, we developed a multi-layer taxonomy of digital technologies that includes eight dimensions structured along the layers of established modular architectures, i.e. service, content, network, and device. Based on our taxonomy, we also identified seven archetypes of digital technologies by means of a cluster analysis. To revise and evaluate our artefacts, we classified 45 digital technologies from the Gartner Hype Cycle of Emerging Technologies and conducted evaluation rounds with other researchers. Our results contribute to the descriptive knowledge on digital technologies. They enable researchers and practitioners to classify digital technologies on two levels of aggregation and to make informed decisions about their adoption.