What is the brief definition of calling codes?

Answer 1

A calling code, also called a telephone area code or just area code, is a number that identifies a particular geographic area for telephone numbering purposes. For example, in the UK, telephone area code 01244 identifies telephone numbers from the city of Chester and nearby areas.

A calling code for an entire country is called a telephone country code. For example, the telephone country code for North Korea is +850.

(The plus sign means "insert your international access prefix here." From a GSM mobile phone, you can enter the number in full international format, starting with the plus sign. The most common prefix is 00, but North America (USA, Canada, etc.) uses 011, Japan uses 010, Australia uses 0011, and many other countries use different prefixes.)

Answer 2

"Calling codes" is a catch-all term for telephone country codes, area codes, and dialing prefixes. They are the numbers that you dial to access a telephone number in a particular country or city.