The International dialing sequence is essentially the same when dialing from anywhere, to anywhere.
First, dial the IDD (International Direct Dialing Number).
For example, the IDD to call from the United States is 011. Other countries have different numbers, or
may have more than one IDD, depending on the carrier or type of service. Make sure you use the correct IDD.
Next, dial the country code of the country you are trying to call.
Every country has a country code, which you dial after theh IDD. In some cases, the country code is
shared among countries. For example, the United States, Canada, and much of the Caribbean and Guam use country code 1.
Third, dial the city/area code (if any) for the number you are dialing.
Smaller countries may not use city codes or area codes, while larger countries have hundreds of them. Because of
the tremendous growth of global telecommunications, city codes and area codes change or are added frequently.