That is true, but incomplete.
Rosh Hashanah is not mainly a party about a calendar turning over. It opens the most searching season in the Jewish year: a period of judgment, repentance, prayer, and moral inventory that culminates in Yom Kippur.
Rosh Hashanah begins the High Holy Day season
Britannica defines Rosh Hashanah as the major two-day observance that marks the religious New Year on the first day of Tishri. More importantly, it begins the Ten Days of Repentance, also called the Days of Awe, which end on Yom Kippur.
That is why the holiday feels serious even when it includes festive foods and family gathering. The question is not only what year it is. The question is what kind of person one has been and what kind of person one intends to become.
The shofar is a call to wake up
Britannica notes that the shofar, a ram's horn, is blown during Rosh Hashanah as a call to spiritual awakening.
That is the right way to think about it. The shofar is not background music. It interrupts routine. It turns the holiday into a summons. Jewish tradition hears in it a demand to stop drifting and pay attention to judgment, memory, responsibility, and change.
The language of judgment is central
Britannica explains that Rosh Hashanah is linked in liturgy and tradition with the opening of the books of life and death. The imagery is stark because the day asks worshippers to think in ultimate terms.
This does not mean Judaism treats Rosh Hashanah as mere fear. It means the holiday assumes that moral life matters, that actions have consequences, and that a person should not sleepwalk through that fact.
Customs matter because they give reflection a social form
Rosh Hashanah is also marked by recognizable ritual habits. People greet one another with wishes for a good year. Many families eat apples dipped in honey as a sign of hope for sweetness in the year ahead. Prayer services expand, and synagogue attendance rises even among Jews who are not regular worshippers the rest of the year.
Those customs matter because they make reflection communal rather than private.
Why it still matters
Rosh Hashanah lasts because nearly every serious life needs a season of review. Judaism gives that need a liturgical shape. It ties memory to repentance, repentance to prayer, and prayer to action before the year moves on.
The shortest accurate answer
Rosh Hashanah is the Jewish New Year, but more precisely it is the opening of the High Holy Day season and the beginning of the Ten Days of Repentance that lead to Yom Kippur.
It is a holiday of judgment, spiritual awakening, and moral review.