International Dialing Codes are numerical prefixes used to make phone calls between different countries. Each country has a unique code, which is added before the local phone number when dialing internationally. For example, the code for the United States is +1, while India uses +91. These codes help telephone networks route calls correctly across borders. To call a foreign number, you typically start with a "+" or "00," followed by the country code and then the local number. Understanding these codes is essential for effective global communication.