This book examines the English Lingua Franca (ELF) uses in a corpus of online and scripted video-game interactions. While research generally explores the playful and technological aspects of computer-mediated communication, this study focuses on the strategies of cooperation, language simplification and authentication, lexical creativity and meaning negotiation that are generally activated within the «community of practice of gamers» to facilitate cross-cultural conversations. The scripted exchanges, instead, are examined by means of the ALFA Model (Analysis of Lingua Franca in Audiovisual texts), which is devised to enquire into the extent to which the non-native participants¿ language variations are part of the multimodal actualisation of the cognitive construct of «non-native speakers», to which authors resort in order to prompt specific reactions on the part of the receivers. Finally, since the participants¿ turns in both online and scripted interactions are visually represented as written messages on screen, this research also contributes to the development of the description of written ELF variations, so far not thoroughly explored in the literature.