Kol Nidre is an ancient legal formulation that means "All Vows." During its recitation a person asks God to annul any promises that may have been unintentionally made to God (not to other people) during the preceding year. Over the centuries several attempts have been made to eliminate Kol Nidre from the standard Yom Kippur service - partially because of its legal origins and partially because anti-Semites have misinterpreted Kol Nidre and attempted to use it as an example of Jews being untrustworthy. However, Kol Nidre is sung to such a hauntingly beautiful melody that for many Jews hearing its recitation is a defining part of the Yom Kippur experience.
Learn more about Kol Nidre's origins and meaning in: What Is Kol Nidre?
Image credit: Getty Images/Steve Allen