Thanksgiving Day is a harvest festival celebrated primarily in the United States and Canada. Traditionally, it is a time to give thanks for the harvest and express gratitude in general. While perhaps religious in origin, Thanksgiving is now primarily identified as a secular holiday. 
The date and location of the first Thanksgiving celebration is a topic of modest contention. The traditional "first Thanksgiving" is the celebration that occurred at the site of Plymouth Plantation, in 1621. The Plymouth celebration occurred early in the history of what would become one of the original thirteen colonies that became the United States. The celebration became an important part of the American myth by the 1800s. This Thanksgiving, modeled after celebrations that were commonplace in contemporary Europe, is generally regarded as America's first. Elementary school teacher Robyn Gioia has argued that the earliest attested "thanksgiving" celebration in what is now the United States was celebrated by the Spanish on September 8, 1565 in what is now Saint Augustine, Florida. Today, Thanksgiving is celebrated on the fourth Thursday of November in the United States and on the second Monday of October in Canada. Thanksgiving dinner is held on this day, usually as a gathering of family members and friends.
I figured we can all use this info on Thanksgiving. Overall... Just give thanks for your family, friends, dogs, cats, life, people who you love and don't like so much. Just give thanks no matter what it is... It just feels good man!