This chapter introduces the reader to the complexities of revision analysis and problematises the issues surrounding the development of revision taxonomies, 'online' revision analysis and the categorisation of online revisions. For the reader unfamiliar with the writing process, the chapter begins by overviewing the writing process. This introduction to the writing process provides the reader unfamiliar with writing and revision processes with a ground for understanding of the complexity of revision and the overview of revision presented in this chapter. After reading this chapter, the reader will have the necessary understanding of the writing and revision processes to follow the arguments relating to the development of an online revision taxonomy and online revision categorisation presented by Lindgren and Sullivan (this volume, Chapter 9).