Memorial Day is an American holiday, observed on the last Monday of May, honoring the men and women who died while serving in the U.S. military. 

Originally known as Decoration Day, it originated in the years following the Civil War. But in 1968, Congress passed the Uniform Monday Holiday Act, which established Memorial Day as the last Monday in May in order to create a three-day weekend for federal employees. The change went into effect in 1971. The same law also declared Memorial Day a federal holiday.

Many Americans observe Memorial Day by visiting cemeteries or memorials, holding family gatherings and participating in parades. Unofficially, it marks the beginning of the summer season.