The Old Testament was written between 1400 BC and 400 BC. It is divided into five sections - the Pentateuch (Genesis to Deuteronomy), historical books (Joshua to Esther), poetic books (Job to Song of Solomon), major prophets (Isaiah to Daniel), and minor prophets (Hosea to Malachi). Scholars use internal evidence like writing style, people and places mentioned, as well as external evidence like historical records, to determine the approximate dates of authorship for each book. Dating is also done through cross-referencing between biblical books and historical events described within.