Rosh Hashanah (רֹאשׁ הַשָּׁנָה) is the Jewish New Year.
This year on September 15th, we will be celebrating the 5784nd anniversary of the creation of the world, but more precisely, the creation of Adam and Eve. The holiday is on the first and second day of tishrei. Then begins the ten days of penance, and lasts until Yom Kippur, the Day of Atonement.