Veterans Day is an official United States holiday that honors people who have served in the U.S. Armed Forces, also known as veterans. It is a federal holiday that is observed on November 11. It coincides with other holidays such as Armistice Day and Remembrance Day, which are celebrated in other parts of the world and also mark the anniversary of the end of World War I. The United States also originally observed Armistice Day; it then evolved into the current Veterans Day holiday in 1954. Veterans Day is not to be confused with Memorial Day; Veterans Day celebrates the service of all U.S. military veterans, while Memorial Day is a day of remembering the men and women who died while serving. Most sources spell Veterans as a simple plural without a possessive apostrophe.