An “exclave” is a region of a country that is completely separated from the main body of that country, usually by the borders of another country. One classic example of an exclave is Alaska because it is not part of the contiguous continental United States.

An antecedent boundary is the name of a boundary between two states that is created before the area is populated with human society. An antecedent boundary may come to be more relevant in the future if people begin to settle in the area; this is what happened with the boundary between the United States and Canada in Oregon.

An elongated state is a state that is long and narrow. It stretches a long way in one direction (either north-south or east-west) and a very short way in the other direction. Chile is the classic example of an elongated state because it spans thousands of miles top to bottom, but only a few hundred from side-to-side. The opposite of an elongated state is a compact state.

According to the Heartland Theory, a government that controls Central Eurasia (much of Russia, some of Eastern Europe, and the Middle East) is likely to eventually dominate much of the world. Mackinder believed that this region was central to interaction between Europe and Asia and to the rest of the world. Most contemporary geographers disagreed with him.

A perforated state is a state that completely surrounds another state. Two classic examples are Italy, which completely surrounds San Marino and the Vatican, and South Africa, which completely surrounds Lesotho. Due to the vulnerability of the surrounded state, it is often vital for that state to maintain good relations with the perforated state that surrounds them.

When a line of latitude or longitude is used to delineate the political barrier between two states we call that boundary a “geometric boundary.” One famous example of a “geometric boundary” is the 49th parallel between the United States of America and Canada.

A prorupted state is a state that has a primary body of territory that comprises most of the state, but that also has a long extension that can dramatically increase the territorial power and significance of the country. The classic example of a prorupted state is Thailand.

The geographic term for a country that is completely surrounded by the territory of more than one other country and has no direct access to the sea is “landlocked.” Being landlocked is generally considered to be a major disadvantage for a country because that country must rely on another country for any goods that are transported by sea. Many wars have been started by landlocked countries seeking to carve a path to the ocean through another country's territory.

A fragmented state is a state whose territory is physically divided into several distinct segments. This presents a unique set of problems to the government and administration of fragmented states because there are physical barriers that prevent ease of transportation and limit the control that can be wielded by the centralized government. Two classic examples of fragmented states are Indonesia and the Philippines because they are states comprised of a few big islands and dozens of smaller islands.

Alaska is an example of an exclave because it is a region of the United States that is completely separate from the main body of the United States. It can be helpful to think of the prefixes "ex-" and "en-" when considering the meaning of “exclave” and “enclave.” The prefix "ex-" means outside of and the prefix "en-" means inside of.