Memorial Day is a federal holiday in the United States for honoring and mourning the military personnel who have died while serving in the United States Armed Forces. It is observed on the last Monday of May each year.

The holiday, originally known as Decoration Day, started after the Civil War to honor the Union and Confederate soldiers who died during the Civil War. By the 20th century, Memorial Day had been extended to honor all Americans who have died while in the military service.

On Memorial Day, it is customary to fly the flag at half-staff until noon, and then raise it to the top of the staff until sunset in honor of the nation’s battle heroes. Many people visit cemeteries and memorials, particularly to honor those who have died in military service. It’s also common for volunteers to place an American flag on each grave in national cemeteries.

The holiday is often seen as the unofficial start of summer, with many families gathering for picnics, barbecues, and sporting events. However, the true purpose of Memorial Day is to remember and honor those who have made the ultimate sacrifice for their country.