Yom Kippur falls on the eve of the tenth day of Tishrei, ten days after Rosh Hashonah. It starts at sunset and finishes one hour after sunset. As it is a Shabbat, it is a day of rest, just as G-d rested after creating the earth. It is the only day of the year that there are five services in the synagogue, starting with Maariv which is the evening service with Kol Nidre and finishing with Ne'ilah, the single sound of the 'shofar' marks the end of this holy day.
Yom Kippur is a fast so, no eating or drinking for 25 hours. Children who have not celebrated their Barmitzvah or Batmitzvah are considered to young to fast, together with those who are unwell or ladies who are expecting babies. The final meal before the the Fast is a festive occasion, usually including chicken soup, chicken and challah, it is a good idea to drink plenty of water and not have too much salt on food as that can make you very thirsty. After the Fast ends it is usual to eat a selection of cold foods that have been previously prepared.
Yom Kippur is a time when we reflect about all we have done wrong over the past year and ask forgiveness, promising ourselves not to make the same mistakes in the coming year. What is quite interesting is that in biblical times, priests used to take people's sins and put them on to an animal, and when the animal was sacrificed their sins were released into the wilderness. That is where the word scapegoat comes from, which is commonly used today, and means someone who is innocent taking the blame for something they did not do.