This chapter describes the history of the Septuagint and its revisions. It also describes the present important aspects of Septuagint study. In the Septuagint one also finds biblical books that are often labelled deuterocanonical or apocryphal. The Greek fragments of biblical text found among the Dead Sea scrolls could be an indication that Greek texts were also read and/or produced in places other than Alexandria. The study of the Septuagint has contributed to the knowledge of the Judaism of its time. Not only does the Septuagint help to define and understand Hellenised Judaism, it also contains many an interpretation that helps to understand the cultural context. A thorough knowledge of the semantics, style and syntax of a document can help editors of manuscripts to reconstruct lost sections of text and scholars that are reconstructing Vorlagen of Greek texts.