Language is a key resource in the formation of online communities, which are in turn central to an understanding of contemporary social relations. This study looks at TED.com, an educational video-hosting platform with few in-built community-building functionalities, to explore the potential for users to affiliate through their language choices. Grounded in Systemic Functional Linguistics, the study uses the Appraisal framework, extended using corpus linguistic methods, in order to analyse users’ reactions to TED videos. The study shows that online participants use evaluative language to align with certain ideas and, based on these affinities, form affiliations characterized by sociability and solidarity. These affiliations raise important questions about the conception of ‘community’ in twenty-first century society
