Dialing codes, also known as telephone country codes, are numerical prefixes used to identify specific countries or regions when making international phone calls. Each country has a unique code, which is typically preceded by a "+" sign. For example, the dialing code for the United States is +1, while India has the code +91. When dialing internationally, you must first enter the exit code of your country, followed by the country code, and then the local phone number. This system helps ensure that calls are routed correctly across different telecommunications networks worldwide.