Today few people remember the biblical name of Yom Teruah and instead it is widely known as "Rosh Hashanah" which literally means "head of the year" and hence also "New Years". The transformation of Yom Teruah (Day of Shouting) into Rosh Hashanah (New Years) is the result of pagan Babylonian influence upon the Jewish nation.
On the 1st day of the Seventh month (Tishrei) the Torah commands us to observe the holy day of Yom Teruah which means "Day of Shouting" (Lev 23:23-25; Nu 29:1-6). Yom Teruah is a day of rest on which work is forbidden. One of the unique things about Yom Teruah is that the Torah does not say what the purpose of this holy day is.
Yom Teruah is mentioned in the following biblical passages:
Lev 23:23-25 "And YHVH spoke unto Moses saying, Speak to the Children of Israel saying, In the Seventh month on the first of the month will be a day of rest (Shabbaton) for you, a Remembrance Shouting, a holy convocation. You shall do no work and you will bring a fire sacrifice to YHVH."
Nu 29:1-6 "And in the Seventh month on the first of the month will be a holy convocation for you; you shall do no work, it will be a Day of Shouting for you. [List of Sacrifices for Yom Teruah]."