The main purpose of Yom Kippur is to encourage repentance. The holiday is observed with a 25-hour long fasting, thus fulfilling the requirement of making our body uncomfortable on this day. Also known as Shabbat Shabbaton, when not only the prohibitions for Shabbat apply, but it is forbidden to eat, drink, bathe or wash, use any perfumes, wear comfortable leather shoes, and to engage in marital relations. Compliance with the prohibitions is not an end; it is a means for focusing our attention on repentance. On the eve of Yom Kippur, prior to fasting, we hold a festive meal to be followed by the Kol nidre prayer in the synagogue and the prayers for Yom Kippur. We spend the next day almost entirely with praying; the end of the fast is signaled by the sound of the shofar.