"The Lord spoke to Moses saying, "Speak to the Children of Israel, saying 'In the seventh month, on the first day of the month, there shall be a day of rest for you, a remembrance with blasts of the Shofar, a holy convocation.'" (Vayikra 23:23)

"Rosh Hashanah" is the day that celebrates the Jewish New Year. It is also more importantly known as Yom HaDin or "The Day of Judgement." On that day, G-d looks at the actions of every individual from the past year, and determines whether or not that person will be written in the Book of Life and earns the blessing of living for another year.

The blowing of the Shofar (a ram's horn) sounds to announce the Creation of the Universe by G-d, and the beginning of His Judgement. The Days of Repentance end eight days later on Yom Kippur, the Day of Repentance.