The Bibliotheca or Myriobiblos was a ninth-century work of Byzantine Patriarch of Constantinople Photius, dedicated to his brother and composed of 279 reviews of books which he had read.

Photios I, also spelled Photius, was the ecumenical patriarch of Constantinople from 858 to 867 and from 877 to 886. He is recognized in the Eastern Orthodox Church as Saint Photios the Great.