Voice over IP

Voice over IP (VoIP) is a methodology and group of technologies for the delivery of voice communications and multimedia sessions over Internet Protocol (IP) networks, such as the Internet. Other terms commonly associated with VoIP are IP telephony, Internet telephony, broadband telephony, and broadband phone service.

The term Internet telephony specifically refers to the provisioning of communications services (voice, fax, SMS, voice-messaging) over the public Internet, rather than via the public switched telephone network (PSTN). The steps and principles involved in originating VoIP telephone calls are similar to traditional digital telephony and involve signaling, channel setup, digitization of the analog voice signals, and encoding. Instead of being transmitted over a circuit-switched network, however, the digital information is packetized, and transmission occurs as IP packets over a packet-switched network. Such transmission entails careful considerations about resource management different from time-division multiplexing (TDM) networks.

Voice-over

Voice-over (also known as off-camera or off-stage commentary) is a production technique where a voice—that is not part of the narrative (non-diegetic)—is used in a radio, television production, filmmaking, theatre, or other presentations. The voice-over is read from a script and may be spoken by someone who appears elsewhere in the production or by a specialist voice talent. It is usually pre-recorded and placed over the top of a film or video and commonly used in documentaries or news reports to explain information. It may also be read live for events such as award presentations.

Techniques

Character device

In Herman Melville's Moby Dick (1956), Ishmael (Richard Basehart) narrates the story and sometimes comments on the action in voice-over, as does Joe Gillis (William Holden) in Sunset Boulevard (1950) and Eric Erickson (William Holden) in The Counterfeit Traitor (1962); adult Pip (John Mills) in Great Expectations (1946) and Michael York in a television remake (1974).

Voice-over technique is likewise used to give voices and personalities to animated characters. Noteworthy and versatile voice actors include Mel Blanc, Daws Butler, Don Messick, Paul Frees, and June Foray.

Google Voice

Google Voice is a telephony service that provides call forwarding and voicemail services, voice and text messaging, as well as US and international call termination services for Google Account customers. The service was launched by Google on March 11, 2009, after the company had acquired the service GrandCentral.

Google Voice provides a U.S. telephone number, chosen by the user from available numbers in selected area codes, free of charge to each user account. Calls to this number are forwarded to telephone numbers that each user must configure in the account web portal. Multiple destination may be specified that ring simultaneously for incoming calls. Service establishment requires a United States telephone number. A user may answer and receive calls on any of the ringing phones as configured in the web portal. During a received call the user may switch between the configured telephones.

Users in the U.S. may place outbound calls to domestic and international destinations. Calls may be initiated from any of the configured telephones, as well as from a mobile device app, or from the account portal. As of August 2011, users in many other countries also may place outbound calls from the web-based application to domestic and international phone numbers.

HTML

HyperText Markup Language, commonly referred to as HTML, is the standard markup language used to create web pages. Along with CSS, and JavaScript, HTML is a cornerstone technology, used by most websites to create visually engaging web pages, user interfaces for web applications, and user interfaces for many mobile applications.Web browsers can read HTML files and render them into visible or audible web pages. HTML describes the structure of a website semantically along with cues for presentation, making it a markup language, rather than a programming language.

HTML elements form the building blocks of all websites. HTML allows images and objects to be embedded and can be used to create interactive forms. It provides a means to create structured documents by denoting structural semantics for text such as headings, paragraphs, lists, links, quotes and other items.

The language is written in the form of HTML elements consisting of tags enclosed in angle brackets (like <html>). Browsers do not display the HTML tags and scripts, but use them to interpret the content of the page.