Rosh Hashanah is the Jewish New Year and the start of ten days of introspection, culminating in Yom Kippur.
Yom Kippur is also known as the Day of Atonement.
Sukkot is known as the harvest festival. Many Jewish people eat and even sleep in sukkot (Hebrew for "booths" or "huts"). Sukkot is celebrated for seven days.
Shemini Atzeret and Simchat Torah are celebrated together on one day by Reform Jews and over two days by Conservative Jews. We celebrate the completion of the annual cycle of reading the Torah.
Hanukkah, also called the Festival of Lights, is celebrated for eight days. We light hanukkiyot (Hanukkah menorahs), spin dreidels, eat latkes, and often celebrate with family and friends.