The United States flag has 13 stripes, representing the original Thirteen Colonies.
The stripes alternate red and white across the flag. The Continental Congress specified thirteen stripes in the Flag Resolution of June 14, 1777, alongside thirteen white stars on a blue field. That resolution created the basic stars-and-stripes design used by the new nation.
The flag briefly had 15 stripes after Vermont and Kentucky joined the Union. The Flag Act of 1794 added both stars and stripes for the two new states. As more states entered, however, Congress decided that the number of stripes should return to 13 and remain fixed. The Flag Act of 1818 established that arrangement.
This produces a useful distinction: the stripes preserve the number of founding colonies, while the stars change as the number of states changes. The current flag has 13 stripes and 50 stars, connecting the Revolutionary era with the modern United States celebrated by America250.