This book seeks to apprehend the process of writing oneself in the digital space. Using literary theories but also sociological theories and the field of communication, the author observes the mechanism of self-writing. Philippe Lejeune's work on autobiography and Oriane Desseiligny's study on digital self-writing devices allow us to understand the relationship between self-writing and digital tools. This study aims to observe the articulation between the evolution of the supports and the impact on the modes of expression. The author also attempts to show how the digital world favors a new way of expressing the "self". By highlighting the impact of the CMO (Computer Mediated Communication) on the writing of oneself and the growing place of the image.