The rapid spread of mobile messaging applications like WhatsApp has its impact on generating special linguistic features archetypal for this type of Computer Mediated Discourse. This study investigates Whatsapp digital language from a discourse analysis approach. The study aims at analyzing the linguistic features and the functions of WhatsApp language among undergraduate students in Mount Kenya University. The study employed a descriptive research design that utilized qualitative research methods. The study employed Computer Mediated Discourse analysis framework. The findings of the study revealed that The findings of the study revealed that linguistic features of WhatsApp digital language are characterized by the use of casual speech and a netlingo among undergraduate students. Linguistic features were reflected in terms of contractions, phonetic spellings, abbreviations, regiolectal contractions, emoticons/Emojis and Punctuation Marks. The data examined revealed that language plays a key role in social media as it is the form of communication. The data revealed the following functions of language: phatic function of language for social connection, Interactional function of language for friendship maintenance, Informational function of language, directive function of language and multlingual function of language. The study recommends that that educators should reconsider how they respond to this new form of writing since the study shows how students are using WhatsApp digital language for academic purposes. The study adds knowledge to linguistics, Computer Mediated Discourse and language and communication.