The Codex Alexandrinus is a 5th-century manuscript of the Bible, written in Greek. It is one of the oldest and most important biblical texts, containing both the Old and New Testaments. The codex is notable for its completeness and its role in the study of early Christianity and biblical translations. This manuscript is housed in the British Library in London and is considered a key witness to the text of the Bible. It is part of a group of ancient manuscripts known as the Alexandrian text-type, which significantly influenced later translations, including the King James Version.