Country calling codes
From Eshralopedia
This page outlines the international dialing codes for countries and territories around the world.
The Code
The international dialing code was created by using a simple code: +ZX(x)
The Z in the code is replaced by a number from 1-9, which represent one of the 9 zones around the world. Each nation or territory belongs to only one Zone.
The X(x) in the code is replaced by the countries number within their own Zone (see map at top of page). These were originally designated 1-9 within each Zone, however due to new nations and territories being introduced into the international dialing code system soon after it was developed, it was decided that there would be additional numbers of 01, 02, 03... and so on. Some nations may choose the further divide their code up within each territory. For example using +ZX(z) where ZX is the international part and the x is to signify a state or province. Many nations have decided not to do this, as it can cause confusion for international callers and they prefer instead to use local area codes within the country as a substitute.
Before the +ZX(x) a nation must use a number combination to distinguish that they are calling to an international number. Many countries, such as Savam use an '00' code, which mean someone in Savam calling someone in Ragnam would dial 0011 at the beginning of the number.
Brief overview
Country calling codes form a prefix code, hence they can be organized as a tree:
