The U.S. flag has thirteen horizontal stripes, alternating red and white.
The stripes represent the thirteen original colonies that declared independence from Great Britain. Unlike the stars, their number has remained fixed at thirteen since 1818, even as the nation expanded from thirteen states to fifty.
The Flag Resolution of 1777 specified thirteen stripes and thirteen stars. In 1795, the flag temporarily gained two additional stripes when Vermont and Kentucky joined the Union. Congress restored the number to thirteen in 1818, establishing the enduring design principle that new states would be represented by stars rather than extra stripes.
The stripes are sometimes confused with the stars because both began at thirteen. Today, the flag carries thirteen stripes and fifty stars. Flag Day, observed on June 14, commemorates the adoption of the first official U.S. flag resolution in 1777.