Tishah B'av, also spelled Tisha B'av or Tischa B'av, is a Jewish day of mourning and fasting that commemorates the destruction of the First and Second Temples in Jerusalem. Synonyms for Tishah B'av may include the Ninth of Av, the Day of Calamity, or the Day of Wailing. It is a solemn occasion when Jews remember the tragedies that have befallen their people throughout history. Synonyms for this day may also include the Fast of Av, the Black Fast, or the Fast of the Fifth Month. Tishah B'av serves as a reminder of the importance of repentance, mourning, and maintaining hope for a future redemption.