Some countries of the world use a leading ‘8’ in the call sequence.
In Russia, Kazakhstan, Belarus, Lithuania, Azerbaijan, Turkmenistan, Uzbekistan, Tajikistan, Abkhazia, and South Ossetia, the leading ‘8’ in a phone number is called a ‘trunk prefix.’ It is used to notify the circuits of the telephone network that the number being called is in another region of the country.
It is similar in function to a leading ‘0’ that is used in many countries in Europe, Asia, and Africa, and the leading ‘1’ that is used within the North American Numbering Plan (NANP).