In 1916, when President Woodrow Wilson officially established Flag Day, it marked the anniversary of the Second Continental Congress creating a unified colonial army and the Continental Colors for what became the American flag.

Two years after forming the army in 1775, Congress passed a resolution to differentiate the flag from the one flown by the British. It established that “the flag of the United States be 13 stripes, alternate red and white,” and that “the union be 13 stars, white in a blue field, representing a new constellation.

More than 100 years later, the U.S. continues to observe Flag Day. Here are some facts about the flag and the day honoring it.