A codex is the earliest form of a manuscript, bound as a book, especially of a classical work or scripture. The word comes from the Latin word meaning tree-trunk. The most famous codices are Biblical manuscripts, such as the fourth-century Codex Sinaiticus and Codex Vaticanus and the fifth-century Codex Alexandricus. The term may also refer to a collection of laws.
The Codex Sinaiticus is a manuscript of the Greek Bible found in two parts in 1849 and 1859. It contains all the New Testament and about a third of the Old Testament, and was bought by the British Museum in 1933.