http://en.wikipedia.org/wiki/Thanksgiving

The pattern of the Thanksgiving celebration has never changed through the years. The big family dinner is planned months ahead. On the dinner table, people will find apples, oranges, chestnuts, walnuts and grapes.There will be plum pudding, mince pie, other varieties of food and cranberry juice and squash. The best and most attractive among them are roast turkey and pumpkin pie. They have been the most traditional and favorite food on Thanksgiving Day throughout the years. 　　Everyone agrees the dinner must be built around roast turkey stuffed with a bread dressing[3] to absorb the tasty juices as it roasts. But as cooking varies with families and with the regions where one lives, it is not easy to get a consensus on[4] the precise kind of stuffing for the royal bird.Thanksgiving today is, in every sense, a national annual holiday on which Americans of all faiths and backgrounds join in to express their thanks for the year' s bounty and reverently ask for continued[5] blessings.

hanksgiving Day is a harvest festival. Traditionally, it is a time to give thanks for the harvest and express gratitude in general. It is primarily a North American holiday which has generally become a national secular holiday with religious origins. The date and location of the first Thanksgiving celebration is a topic of modest contention. Though the earliest attested Thanksgiving celebration was on September 8, 1565 in what is now Saint Augustine, Florida,the traditional "first Thanksgiving" is venerated as having occurred at the site of Plymouth Plantation, in 1621. Today, Thanksgiving is celebrated on the second Monday of October in Canada and on the fourth Thursday of November in the United States. Thanksgiving dinner is held on this day, usually as a gathering of family members.