Washington, D.C., formally the District of Columbia and commonly referred to as Washington, "the District", or simply D.C., is the capital of the United States. The states of Maryland and Virginia each donated land to form the federal district. Washington, D.C., had an estimated population of 646,449 in 2013, the 24th most populous place in the United States. The District is bordered by Montgomery County, Maryland, to the northwest; Prince George's County, Maryland, to the east; and Arlington and Alexandria, Virginia, to the south and west.
The name Washington was to honor the first president of the USA, George Washington. The name Columbia is in reference to Christopher Columbus.
DC stands for District of Columbia. It is called District of Columbia, because it was built on land of the Territory of Columbia, a 10 square mile piece of land, that used to be part of Virginia and Maryland. The territory of Columbia was named such after Christopher Columbus.
Washington, D.C., the capital of the United States of America, has been known by a variety of nicknames, aliases, sobriquets and slogans, both officially and unofficially, now and in the past. Washington, D.C., formally the District of Columbia and commonly referred to as Washington, "the District", or simply D.C., is the capital of the United States.