"Speak to the children of Israel and say: The first day of the seventh month shall be a day of rest for you. It is a holy holiday for remembrance [and] sounding [the shofar]. You shall not do any work and you shall bring a fire offering to G-d."
VaYikra (Leviticus) 23:24

"The first day of the seventh month shall be a sacred holiday to you when you may not do any mundane work. It shall be a day of sounding the horn."
BaMidbar (Numbers) 29:1

The holiday of Rosh HaShana is the anniversary of the creation of the world and the beginning of the Kingdom of G-d. On this day we reaffirm our acceptance of G-d as our King. G-d judges all of His creations on this day and decides on their fate in the coming year. Rosh HaShana is two days long even in Israel.

The holiday of Rosh HaShana is a day of intense and lengthy prayer and restrained rejoicing. We rejoice in our acceptance of G-d's Kingship but our rejoicing is subdued by our recognition of the great judgment which is taking place.

The Shofar

The shofar is made from an animal horn, preferably from a ram. A cow's horn is not acceptable. Nor are the antlers of a deer or similar animals who's horns are a solid piece.

There are three sounds made with the shofar:
Tekiah - One long blast.
Shevarim - Three shorter blasts.
Teruah - A series of quick blasts.

While, of course, the reason we blow the shofar is because G-d commanded us to do so, there are many meanings and messages which are present in the blowing.

1. The sound of the shofar serves as a "wake-up" call to arouse our souls to repentance.

2. Rosh HaShana is the anniversary of the creation of the world and is therefore the anniversary of the beginning of G-d's Kingdom. Thus, we blow the shofar to show that we accept G-d as our king, as it says in Tehillim (Psalms) 98:6, "With trumpets and the sound of the shofar make a call out before the King, G-d".

3. The sound of the shofar was present when we received the Torah at Mount Sinai as it says in Shemot (Exodus) 19:16, "And it came to pass on the third day in the morning, that there was thunder and lightning, and a thick cloud upon the mount, and the voice of the shofar extremely loud; so that all the people that were in the camp trembled." Thus when we hear the shofar we are reminded to strengthen our commitment to the Torah.

4. The sound of the shofar (which is usually made from the horn of a ram) reminds of when Abraham tied down his son Itzchak to sacrifice him to G-d as G-d had told him and G-d stopped him at the last second and gave him a ram to sacrifice instead. From this we learn that just as our ancestors Abraham and Itzchak were willing to make such a great sacrifice to serve G-d, we must also be willing to make such sacrifices.

Symbolic Foods

1. We dip an apple in honey and say "May it be Your will, G-d, that You renew for us a good and sweet year."

2. We eat a pomegranate and say "May it be Your will, G-d, that our merits increase as the seeds of a pomegranate."

3. We eat the head of a sheep (or fish) and say, "May it be Your will, G-d, that we be as the head and not as the tail."

4. We eat fish and say, "May it be Your will, G-d, that we be fruitful and multiply like fish."

In general, it is customary to eat sweet foods and avoid bitter foods. It is also customary to avoid eating nuts on Rosh HaShana. There are two reasons for this custom. One is because nuts increase salivation which can interfere with our prayers and, secondly, because the numerical value of the Hebrew word for nut is equal to the the numerical value for the Hebrew word for sin.

Tashlich