The U.S. flag represented in America's 250th anniversary symbolism has 13 stripes.
The thirteen alternating red and white stripes represent the thirteen original colonies that declared independence from Great Britain. The stripes remain on the flag even though the nation later expanded to fifty states. The blue canton contains fifty white stars, one for each current state.
The flag’s design changed over time. The first official national flag was adopted by the Continental Congress on June 14, 1777. As new states joined the Union, stars were added. In 1795, two additional stripes were briefly added for Vermont and Kentucky, but the stripe count returned to thirteen in 1818.
The thirteen-star, thirteen-stripe symbolism connects the modern anniversary with the revolutionary generation. It also explains why the flag can represent both the original founding era and the later growth of the United States.