One of my favorite holidays!

The Festival of Sukkot begins on Tishri 15, the fifth day after Yom Kippur. It is quite a drastic transition, from one of the most solemn holidays in our year to one of the most joyous.

The word "Sukkot" means "booths," and refers to the temporary dwellings that we are commanded to live in during this holiday. The name of the holiday is frequently translated "The Feast of Tabernacles," which, like many translations of technical Jewish terms, isn't terribly useful unless you already know what the term is referring to. The Hebrew pronunciation of Sukkot is "Sue COAT," but is often pronounced as in Yiddish, to rhyme with "BOOK us."

Like Passover and Shavu'ot, Sukkot has a dual significance: historical and agricultural. The holiday commemorates the forty-year period during which the children of Israel were wandering in the desert, living in temporary shelters. Sukkot is also a harvest festival, and is sometimes referred to as Chag Ha-Asif, the Festival of Ingathering.

In honor of the holiday's historical significance, we are commanded to dwell in temporary shelters, as our ancestors did in the wilderness. The commandment to "dwell" in a sukkah can be fulfilled by simply eating all of one's meals there; however, if the weather, climate, and one's health permit, one should live in the sukkah as much as possible, including sleeping in it.

It is common practice, and highly commendable, to decorate the sukkah. In the northeastern United States, Jews commonly hang dried squash and corn in the sukkah to decorate it, because these vegetables are readily available at that time for the American holidays of Halloween and Thanksgiving. Building and decorating a sukkah is a fun, family project, much like decorating the Christmas tree is for Christians.

Many Americans, upon seeing a decorated sukkah for the first time, remark on how much the sukkah (and the holiday generally) reminds them of Thanksgiving. This is not entirely coincidental. Our American pilgrims, who originated the Thanksgiving holiday, were deeply religious people. When they were trying to find a way to express their thanks for their survival and for the harvest, they looked to the Bible for an appropriate way of celebrating and based their holiday in part on Sukkot.

http://www.jewishvirtuallibrary.org/jsource/Judaism/holiday5.html