Horologion – book of the liturgy of the Hours, a set of liturgical services distributed throughout the whole day. It includes:
Vespers (daily, Resurrectional, Great with vigil
Small Compline (Great Compline is celebrated three times a year on Christmas Eve, Epiphany Eve, on the Eve of the Annunciation, some days of the Great Fast)
Noctum (daily, Saturday, Sunday)
First Hour – celebrated around 6 am or right after the Matins
Third Hour – at 9 am
Sixth Hour – at 12 pm
Ninth Hour – at 3 pm
The Typica – outside of the Great Fast this service can be taken after the sixth hour, and during the Great Fast – after the ninth hour.
Services of the eight tones – depending on the date for the feast of the Pasch; the eight tones interchange weekly one after another after the Pentecost. There are set texts for each day of the week. The book contains the changeable parts for the Horologion, e.g. sticheras, apostichas, troparia, kontakia, canons, etc.
Book of the changeable parts for the season of the Great Fast beginning at the Sunday of the Publican and Pharisee to the Lazarus Saturday of the Passion We
Pentakostarion – book of the changeable parts for the Horologion, celebrated from the Lazarus Saturday to the Pentecost.
Book of the changeable parts for the Horologion, celebrated on the unchangeable feasts of the liturgical year, i.e. feasts of Our Lord and Savior Jesus Christ, the Theotokos, and the Saints. The Liturgical Year in the Byzantine Church starts on September, 1, and it is also called the Indiction.
Euchologion – book of the propers, rubrics, prayers for celebration of the Sacraments, sacramentals, and other special liturgical services, e.g. funerals, blessings of houses, of fruit, etc.
This is the main book of liturgical prayers for a Bishop or Hierarch. Primarily used for a pontifical Divine Liturgy with a Patriarch or other Bishop, but has other prayers as well.
The Psalter, which divides the psalms into groups known as “kathismas”, used in Horologion as changeable parts.
Contains the readings of the Old Testament, especially the prophets.
The book of the epistles read during the Divine Liturgy, distributed for each day of the Liturgical year, and, when prescribed, at the Liturgy of the Hours on specific feasts, e.g. Royal Hours.
Gospel – the readings of the Gospels, distributed throughout the Liturgical Year for every day.