This chapter discusses the written language of digital communication. It considers the reasons for the use of the casual, abbreviated writing style “textese” and the ways that researchers have categorized individual “textisms”. It reviews the pros and cons of the various message collection methods and covers the factors that seem to influence the extent and type of textese that people use. A review of research on the relationship between textese use and literacy skills leads to the conclusion that there is a positive link in children, and no obvious link in adults. The chapter explains how work on the social meaning of textese suggests that message writers are generally careful to vary their writing style to suit their recipient, and that they judge others on their textese use. Finally, it shows the need to continue research on the written language of digital communication as it continues to develop.