Rosh Hashanah is one of Judaism's holiest days and begins at sunset on Wednesday. The two-day celebration marks the start of the Jewish New Year and is filled with traditions, like eating a round challah and saying prayers near a body of water.

Here's what you need to know about Rosh Hashanah and how to greet your Jewish friends or family celebrating this year. Rosh Hashanah begins at sunset on October 2, according to the Old Farmer's Almanac.

Rosh Hashanah, or the Jewish New Year, began on evening Oct. 2 and last through the evening on Oct. 4 this year. Here's what to know about the holiday.