Social network sites are dynamic online sociocultural arenas which give users ample and unprecedented opportunities for selfpresentation through the meshing of language with other semiotic modes. With a focus on Facebook one of the most widelyused online social network sites this book brings together ideas and concepts related to language online multimodality and identity through five topical issues. These include place time profession and education stancetaking and privacy. The book features a discoursecentred online ethnography that provides authentic verbal and multimodal Facebook posts in both Greek and English . These are complemented with insights from interviews with Facebook participants. The examples bring to life various engaging instances of self and otherpresentation on Facebook identifying the ways in which users can locate themselves in terms of place and time announce activities share and broaden their expertise and buttress solidarity among colleagues and fellow students communicate emotions tastes thoughts opinions and assessments control the flow of textual information on their Facebook profiles to secure their privacy. Focusing on discourse manifestations of identity this book also shows how Facebook can function as a space for vernacular literacy practices a silo of relationships a digital memory bank a research tool a knowledge forum a cardiograph of a society and a grassroots channel.