VoIP (short for Voice over Internet Protocol) is an Internet-based telephone system that runs through your DSL connection or a wireless server (you are unable to use VoIP on dial-up Internet connections as it does not provide a fast enough data transfer speed).

Some cell phones, such as BlackBerrys, Droids and iPhones, offer an application that allows you to use a VoIP service on your phone when connected to a Wi-Fi network. With the service, you may make both national and international phone calls that do not go onto your cell phone bill and you are not charged International rates. VoIP does come with a standard, flat monthly fee (typically less than a standard monthly cell phone bill), without any additional charges.