Machzorim

The mahzor (Hebrew: ‎‎, alternately romanised machzor, plural mahzorim, pronounced [maχˈzor] and [maχzoˈrim], respectively) is the prayer book used by Jews on the High Holy Days of Rosh Hashanah and Yom Kippur. Many Jews also make use of specialized mahzorim on the three "pilgrimage festivals" of Passover, Shavuot, and Sukkot. The mahzor is a specialized form of the siddur, which is generally intended for use in weekday and Shabbat services.

The word mahzor means "cycle"; the root means "to return". It is applied to the festival prayer book because the festivals recur annually.

Some of the earliest formal Jewish prayerbooks date from the tenth century; they contain a set order of daily prayers. However, due to the many liturgical differences between the ordinary, day-to-day services and holiday services, the need for a specialized variation of the siddur was recognized by some of the earliest rabbinic authorities, and consequently, the first mahzorim were written incorporating these liturgical variations and additions.

The mahzor contains not only the basic liturgy, but also many piyyutim, which are liturgical poems specific to the holiday for which the mahzor is intended. Many of the prayers in the mahzor, including those said daily or weekly on the Sabbath, have special melodies sung only on the holidays. Most mahzorim contain only text and no musical notation; the melodies, some of which are ancient, have been passed down orally.

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