Answer :
Thanksgiving day is a national holiday celebrated primarily in the United States and Canada as a day of giving thanks for the blessing of the harvest and of the preceding year.
Thanksgiving Day is a day when people thank for good harvests and all the preceding year in general. It's a national and cultural holiday celebrated on 4th Thursday of November each year. The roots of the Thanksgiving Day reach the times of English Reformation. It's unknown when and where the first Thanksdiving Day celebration took place, but we assume it comes from the first thanksgiving of the Plymouth Colony in 1621.