Telephone calls within US are considered local (within the area of the caller) or long
distance (outside the area of the caller). Each local region is assigned a code. The phone numbers are accordingly denoted as (area code)-123-4567, where 123-4567 is your actual phone number.

Local calls within a short region are free unless made from a public pay phone. Each local region is assigned an "area code". If the call is outside your area you need to dial 1-(area code)-123-4567, which is the long distance call. Long distance calls are charged at varying rates, depending on how you make the call (which long distance carrier/company you use), for how long you speak, and the time of the day.