The International Telecommunication Union (ITU), in its International Radio Regulations, divides the world into three ITU regions for the purposes of managing the global radio spectrum. Each region has its own set of frequency allocations, the main reason for defining the regions.
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The definition of the European Broadcasting Area uses some of the definitions of Region 1.
For convenience the regions are further divided into a total of 90 zones. While often following political boundaries, in more remote land and sea areas these are often defined to be roughly equal in size and so can have very low populations. As examples, Antarctica is divided into seven zones, and in one Pacific Ocean zone the only land area is tiny Minami Torishima.[2] For certain awards and contests amateur radio operators may attempt to contact as many zones as possible.