An area of land (or occasionally sea) that is defined by political, military or cultural control.
A territory is a politically defined area of land.
With such a flexible definition, there are many types of "territory".
A dependent territory is a region of land that is controlled by sovereign state, but is not part of that state. Examples include "Puerto Rico", and "Jersey".
An occupied territory is a region that is under military control by a different state. Examples include the Golan Heights, and Berlin after the end of the war.
Unclaimed territory is a region of land which no country has declared that they own.
A federal territory is a region that is under direct control of a federal government, and not incorporated into one of the provinces that form the federation. Washington DC is a federal territory.
A cultural territory is a region defined by the culture or ethnicity of the people who live there, even if it doesn't have political independence or unity. Examples include Lapland and Kurdistan.
The territory of a sovereign state is the area of land that the state controls.
A sovereign state may also control maritime territory surrounding its coastline. Airspace is another form of territory.
In a war, the various sides may control territory and the line of actual control may differ from the pre-war borders.
