Definition- The core periphery model of development states that as a given region grows and develops from a central starting point, the core, its development is bound to spread to and influence peripheral locations as it continues to expand.
Explanation- As a region expands it will eventually meet another region with a separate economy and or societal factors. In order to continue to grow a given region must “engulf” surrounding regions so that it effectively spreads from its initial core to the periphery, outlying locations. These outlying locations are either influenced or completely overcome by the new incoming governances that have spread from the initial core.
Example- The most notable example of the core periphery model of development can be seen in the development of countries. The MDCs centered closely together, such as in Europe and North America which act as a large core, have spread their influence throughout LDCs which comprise the periphery.
Heartland Theory: (Halford Mackinder) early 20th c. theory that claimed whichever state controlled the resource-rich “heartland” of Eastern Europe could eventually dominate the world. It would suggest that not the United Kingdom (an ocean-based empire), but Russia (which was becoming communist) would be in a position to achieve this dominance. "Who rules East Europe commands the Heartland; who rules the Heartland commands the World-Island (Europe, Asia & Africa); who rules the World-Island controls the world."
Rimland Theory: (Nicholas Spykman) mid 20th c. theory that the domination of the coastal fringes of Eurasia (the “rimland”) would provide the base for world conquest (not the “heartland”).