"Jews traditionally gather in synagogues on Rosh Hashanah for extended services that follow the liturgy of a special prayerbook, called a mahzor, that is used during the Days of Awe. At specific times throughout the service, a shofar, or ram's horn, is blown. The mitzvah (commandment) to hear the shofar, a literal and spiritual wake-up call, is special to this time of year….A common greeting on Rosh Hashanah is shana tovah u'metukah, Hebrew for 'a good and sweet new year.' Many traditional Rosh Hashanah foods -- apples and honey, raisin challah, honey cake and pomegranate -- are eaten, in part, for this reason." See also the Judaism 101 site.