Aseret Yemei Teshuva

The first ten days of seventh month of the Jewish year (from the beginning of Rosh Hashana until the end of Yom Kippur) are known as the Aseret Yemei Teshuva. During this time it is "exceedingly appropriate" for Jews to practice "Teshuvah", which is examining one's deeds and repenting for sins committed against both God and one's fellow man in anticipation of Yom Kippur. This repentance can take the form of additional supplications, confessing one's deeds before God, fasting, and self-reflection. On the third day, the Fast of Gedalia is celebrated.