Interaction and collaboration are often used in foreign language teaching including writing. However, they are applied to varying degrees for different languages. The methods have been used especially in the writing of English as a second language [Berg, 1999], but have rarely been used in Swahili. In this paper therefore, I investigate the effects of Facebook chat on essay writing in Swahili. I specifically try to find out (i) the nature of interaction and collaboration that students have when they use Swahili during their Facebook chat and (ii) the type of language that students transfer from their Facebook chat to their essay writing in Swahili. This study and the writing of this paper is guided by interactionist [Long, 1996] and collaboration theories [Vygotsky, 1978] so as to gain a better understanding of the communication of such a structure and how this impacted the essays that the students wrote.