Flag of Delaware	Seal of Delaware

Delaware is one of five Middle Atlantic States in the United States of America. The name Delaware comes from Thomas West, 3rd Baron De La Warr, after whom the Delaware Bay was named. 2005 population estimates by the Census Bureau place the population of Delaware at 843,524 moving from the 45th most populous state at the 2000 Census to the 46th most populous.

Delaware is the second-smallest state in the United States, Rhode Island being the smallest.

Delaware is bounded to the north by Pennsylvania, to the east by the Delaware River, New Jersey and the Atlantic Ocean and to the west and south by Maryland. Small portions of Delaware are also situated on the far, or eastern, side of the Delaware River Estuary, and these small parcels share land boundaries with New Jersey.

The state of Delaware, together with the Eastern Shore counties of Maryland and two counties of Virginia, form the Delmarva Peninsula, a geographical unit stretching far down the Mid-Atlantic Coast.

The definition of the northern boundary of the state is highly unusual. Most of the boundary between Delaware and Pennsylvania is defined by an arc extending 12 miles (19 km) from the cupola of the courthouse in New Castle, and is referred to as the Twelve-Mile Circle. This is the only true-arc political boundary in the United States (excluding those boundaries defined by latitude, such as the US border with Canada, the border between Oregon and California, etc, which are all arcs centered on the Earth's axis). This border extends all of the way to the low-tide mark on the New Jersey shore, which continues down the shoreline until it again reaches the twelve-mile arc in the south; then the boundary continues in a more conventional way in the middle of the main channel (thalweg) of the Delaware River Estuary. A portion of this arc extends into Maryland to the west, and the remaining western border is a tangent to this arc that runs a bit to the east. The Wedge of land between the arc and the Maryland border remained in dispute until 1921, when Delaware's claim was confirmed.