Geopolitical Explanation of World Metropolises; Reflecting the Conceptual Differences between the Global City and World City

The world cities are new-fangled phenomenon in the world economic system as the nodes where the world economy network connected and are the cause to shape the spaces of flows and makes the new power centers in the world's geopolitics. Meanwhile, the scholars of Peter Taylor's research group identified 54 cities as world cities and classified them on the bases of some deliberative indicators mainly in four field, namely, economics, culture, infrastructures, and communication facilities and categorized them into three ranks: world cities α (10 city), β (10 city), and γ (34 city).On the bases of these researches it seems there is a deep gap between the first and the fifty-fourth cities. Thus we can conclude that there is a basic difference between the "world cities" and the "global cities". Generally speaking, when a metropolis finds her place in the global economy framework and begins to compete with the other cities as a node in the global economy network and in the spaces of flows, it will promote to a "world city" and it occurs only for one among a dozen. This paper attempts to explain the meaning and clarify the concept of these two different terms and explain the differences between the two and at the same time try to eliminate their conceptual ambiguity. The main purpose of the paper is to prove separately the differences between the "world city" and the "global city" and their geopolitical infiltration zone. The indices which have been used here are mainly inspired by Freedman's world city and Sassen's global city hypothesis, with an especial consideration to the Taylor's group 12 indicators. According to Taylor's group researches there are 10 first rank cities which identified as α cities, which six cities of these (New York, London, Paris, Tokyo, Hong Kong, and Singapore) considered as "global city". The other six cities in this group would be considered as global if they could continue the development process they are moving toward. The "world cities" which is considered as β and γ groupings considered as world cities with different rank of importance are subordinate to the four "global cities" mentioned above. Therefore we can see an explicit difference between the concepts of "world city" and "global city". Global cities are the headquarters of global economy and stand at the top of world cities.