Chapter 1 begins with a definition of historical orthography and outlines the purposes, ambitions and boundaries of the subject as a field of knowledge and research inquiry. As part of a discussion on the history of the subject, the chapter summarises relevant thoughts from traditional and more recent students of orthography, while also covering some key changes initiated by the rise of historical sociolinguistics. The introduction also discusses the importance of studying historical orthography as a foundational element in the history of language more broadly.