This chapter points out data visualization’s double role as explorative and communicative means in humanities research. We draw from science and technology studies looking at the mediation process at stake: the interaction between visualization tool and researcher. To emphasize this mediation process and expose the various decisions at its heart we introduce the term ‘data interface’. We highlight how visualizations function as data interfaces and visualization practices allow for interfacing with data biographing a network graph’s ‘life’. Using the lens of the ‘data interface’ underscores that a particular (network) visualization provides just one perspective on the data. Moreover, we examine if and how the used data interfaces encourage scholars to critically position their investigative work, during research processes and communication.