Washington, D.C., is the capital city of the United States of America.
"D.C." stands for the District of Columbia,
the federal district containing the city of Washington.
The city is named after George Washington,
military leader of the American Revolution and the first President of the United States.

The District of Columbia and the city of Washington are coextensive
and are governed by a single municipal government,
so for most practical purposes they are considered to be the same entity
(this was not always the case, though, as there were multiple jurisdictions within the
district as late as 1871, when Georgetown ceased to be a separate city within the District).
However, although there is a municipal government and a mayor,
Congress has the supreme authority.

The centers of all three branches of the U.S. federal government are in the District
as well as the headquarters of most independent agencies.
It serves as the headquarters for the World Bank, the International Monetary Fund,
and the Organization of American States, and other national and international institutions.
Washington is the frequent location of large political demonstrations and protests,
particularly on the National Mall. Washington is the site of numerous national landmarks,
museums, and sports teams, and is a popular destination for tourists.

It is commonly known as D.C., the District, or simply Washington.
Historically, it was called the Federal City or Washington City.
It should not be confused with the state of Washington located in the Pacific Northwest.
To avoid confusion, the city is often called simply D.C.
and the state is often called "Washington State".

The District of Columbia, founded on July 16, 1790,
is a federal district as specified by the United States Constitution.
The U.S. Congress has ultimate authority over the District of Columbia,
though it has delegated limited local rule to the municipal government.
The land forming the original District came from the states of Virginia and Maryland.
However, the area south of the Potomac River (39 square miles or about 100 km²)
was returned, or "retroceded", to Virginia in 1847 and now
is incorporated into Arlington County and the City of Alexandria.
The term "District of Columbia" is derived from an old poetic name for the United States,
Columbia, which has fallen out of common use since the early 20th century.