The Orthodox Church uses eight musical scores or “tones” which are sung in graduating order over the course of eight weeks and then repeated on a regular basis after that. These eight tones, known as the Octoechos in Greek, have existed since the time of the Early Church and most probably originated in Jerusalem or Antioch. Their roots may even predate Christianity, existing to some degree as a testament to ancient Jewish chanting styles.  

In the 8th century, Saint John of Damascus systematically organized these scores into a Book of Eight Tones (Octoechos).  Each tone has its own unique set of melodic formulas, which provide hymnographers a dimension of both structure and diversity as they compose and/or write hymns.