An International Dialing Code is a numerical prefix used to make telephone calls between different countries. Each country has its own unique code, which is added before the local phone number when dialing internationally. For example, the code for the United States is 1, while the code for the United Kingdom is 44. To make an international call, you typically start by dialing a plus sign (+) or 0, followed by the country code, and then the local number. This system helps ensure that calls are routed correctly across global telecommunications networks, allowing people to connect regardless of their location.