The term ‘annotation’ is associated in the Humanities and Technical Sciences with different concepts that vary in coverage, application and direction but which also have instructive parallels. This publication mirrors the increasing cooperation that has been taking place between the two disciplines within the scope of the digitalization of the Humanities. It presents the results of an international conference on the concept of annotation that took place at the University of Wuppertal in February 2019. This publication reflects on different practices and associated concepts of annotation in an interdisciplinary perspective, puts them in relation to each other and attempts to systematize their commonalities and divergences. The following dynamic visualizations allow an interactive navigation within the volume based on keywords: Wordcloud ☁ , Matrix ▦ , Edge Bundling ⊛