Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
Department of English Language and Literature, Shahid Chamran University of Ahvaz, Ahvaz, Iran
Health Information Technology Research Center, Isfahan University of Medical Sciences, Isfahan, Iran
A text messaging service, among other functions of mobile phones, allows mobile phone subscribers to send and receive alphanumeric characters and emoticons. The discourse of the text messages characterizes a kind of interaction, mostly on the boundary between verbal and visual communication. Adopting Halliday's Socio-semiotic Model of Language, this study considered three register variables of filed, mode, and tenor in a text message corpus comprising 2440 text messages collected from 122 medical students at Ahvaz Jundishapur University of Medical Sciences to investigate how the discourse of text message can be affected by the sociolinguistic dimensions of the context of language use. To that end, text messages were analyzed and categorized in term of the social interaction that constituted the content of the messages. The findings revealed that mobile phone text messaging is an asynchronous mode of communication which is characterized with particular register variables, and there are also pragmatic reasons in addition to the technical restrictions for the creation of this register as its users actively and selectively make use of the resources of spoken and written discourses in constructing the message.