The Voice over Internet Protocol is a technology that is used to transmit voice conversations over a data network using the Internet Protocol. Such data network may be the Internet or a corporate Intranet. VoIP enables a router to transmit telephone calls and faxes over the Internet with no loss in functionality, reliability, or voice quality.

This technology allows making telephone calls using a broadband Internet connection instead of a regular (or analog) phone line. Some services using VoIP may only allow calling other people using the same service, but others may allow calling anyone who has a telephone number, including local, long distance, mobile, and international numbers. Also, while some services only work over personal computer or a special VoIP phone, other services allows using a traditional phone through an adaptor.