Voice over Internet Protocol (n)~ The use of the Internet Protocol (IP) for transmitting voice communications. VoIP delivers digitized audio in packet form and can be used to transmit over intranets extranets and the Internet. It is essentially an inexpensive alternative to traditional telephone communication over the circuit-switched Public Switched Telephone Network (PSTN). VoIP covers computer-to-computer computer-to- telephone and telephone-based communications. For the sake of compatibility and interoperability a group called the VoIP Forum promotes product development based onthe ITU-T H.323 standard to transmit multimedia over the Internet.