The thesis works with the fact that communication on social network sites, particularly on Twitter, occurs in short text messages, tweets, which are restricted to the maximum of 140 characters. This leads to the tendency to shorten single and multiword expressions in order to save space and increase the content of sent information. The thesis examines the hypothesis that the number of shortenings on Twitter and their variation may function as a stylistic indicator of tweet genre. It is expected (i) that the number of shortenings in the Twitter sample will be higher compared to other genres and (ii) that the sample will contain more types of shortening, some of which will be characteristic for the tweet genre in general in comparison with the control sample. The research sample of 200 shortenings was collected from two Twitter trends, #Grenfell Tower and #Wimbledon. In the analysis part, the collected sample of shortenings is examined quantitatively, compared to the control sample and separately, interpreted qualitatively. The Appendix contains the complete table listing the meanings of all shortenings. Key words: Twitter, shortening, stylistics, internet linguistics, language of social media

This essay describes a case study of textual communication on the online social mediaplatform Tumblr. The aim of the research was to analyse the communicative functions and thestylistic, sociolinguistic, and pragmatic characteristics of textual discourse on Tumblr. Usingdata gathered on Tumblr, this essay analyses discursive aspects such as function, style, andpragmatics, relating the findings to literature on topics including relevance theory and theoriesof computer-mediated communication and cyberpragmatics. The research found thatdiscourse on Tumblr is largely phatic in nature, with an overwhelming focus on the discussionof shared interests. Such discussion on Tumblr appears to heavily depend on sharedbackground knowledge, which works as a barrier of in-group discursive solidarity andprovides and furthers feelings of connectedness. This study further found that alternative useof style and grammar on Tumblr appears to be largely uniform, suggesting that divergencesfrom standard norms are a way of displaying membership of a group and obtaining covertprestige, rather than a display of linguistic innovation.