The Greek word ευχολογιον literally means "book of prayers." The Slavonic word ''Trebnik'' literally means "book of needs." This type of service book varies widely in contents and arrangements. The most comprehensive edition is the ευχολογιον Ευχολόγιον το μεγα Μέγα or '''Great Euchologion''' contains the prayers of the [[priest]], [[deacon]], and [[reader]] for [[Vespers]], [[Orthros]], and the Divine Liturgy; the six remaining sacraments, and other services of blessings (which in the west are often referred to as ''sacramentals'').