European pioneers of documentation have inspired us to adopt a functional approach to documents. This has led to works on documentality, which is related to the agency and use of documents, and now on documentarity. We define documentarity as a quantifiable quality: not what is a document, but how something can seem documentary. This requires input from writing theories and the study of markup (architext, scripturation) and a comparison between interfaces and the underlying processes (documentarisation, editorialisation). Over the past twenty years, discussions about the nature of documents have often revolved around revisiting the European tradition of documentation. Researchers have taken a new interest in the pioneering theoretical works of authors such as Paul Otlet, Suzanne Briet and Robert Pagès. This has informed our inquiry into the nature of digital documents and data: "Attempts to define digital documents are likely to remain elusive. .. Definitions based on form, format and medium appear to be less satisfactory that a functional approach." 1 1 Buckland, "What is a document?" 1997. Following this, we have set out to define what digital documents do and how they do it, more than what they are in essence. Borrowing from anthropology, Bernd Frohmann defined documentality as the ability to generate traces 2. Maurizio Ferraris 3 also proposed 2 Frohmann, "The documentality of Mme Briet's antelope," 2012, p. 178. 3 Documentality, 2013.Read less <