This past weekend was the Jewish New Year, Rosh Hashanah. You may be asking, "How can it be the new year in September?" Well the answer to your question is because the Judaic calendar is a lunar calendar, meaning it follows how long the moon revolves around Earth. So it is the year 5774 according to the Jewish calendar.
What do Jewish people do on Rosh Hashanah? Well it is two days of praying in temple, and being with family with yummy dinners. It is a time to reflect about past sins and how to improve for the new year.
A classic Jewish tradition during the new year is to eat apples and honey to welcome a sweet new year. Apples and honey in general is quite amazing regardless.
A week later is another holiday called Yom Kippur. This is the holiday follows Rosh Hashanah because Yom Kippur is the holiday where Jews fast and repent for their sins.
I hope that was informative in a crash course on one holiday in Judaism. So... Happy New Year!