In the last decades the Salafiyya as one current within a long history within Islam has come to Europe and become increasingly popular among young Muslims looking for an “authentic” Islam. It is therefore not surprising, that they have taken their interest in religion to the internet and, more specifically, to the computer-mediated environments of social media like chat rooms and online forums. This leads to a series of central questions for the dynamics within the Salafiyya: How do Salafi Muslims approach and use the religious sources (Quran and hadith) in these environments? What kind of religious practices occur in these spaces and how do they relate to offline practices? How are Muslim identities within the Salafiyya formed and maintained in computer-mediated environments? What does this mean for the subjectivity of the individual believer? And how is the religious authority within the Salafiyya affected by these developments? This study answers these questions by employing an innovative methodological approach grounded in practice theory and online ethnography. The data was collected online and offline during extensive and intensive fieldwork in Germany, the Netherlands, and in computer-mediated environement of Muslims inspired by the Salafiya from 2008 until 2011. The study shows how technical and socio-cultural affordances as well as practices reproduce Islam as understood by Salafi Muslims in the specific settings of computer-mediated environments. ; Nederlandse Organisatie voor Wetenschappelijk Onderzoek/Open competitie - programmatisch onderzoek/360-63-040/EU