Videotelephony

Videotelephony is real-time communication that transmits live video and audio between people at separate locations. It combines a camera, display, microphone, speaker, and transmission system.

Video codec: A video codec encodes and decodes digital video, often reducing the data needed for transmission. Compression lets live video travel over networks with limited bandwidth.
Digital camera: A device that captures images and records them as digital data. It supplies the live visual stream.
Alexander Graham Bell: A Scottish-born inventor and engineer associated with the development of the telephone. His telephone made two-way voice communication the foundation for later video calls.
Videoconferencing: A form of videotelephony that connects multiple participants for meetings or collaborative sessions. It extends person-to-person calls to group meetings.
Social presence: The sense that another person is present and accessible during mediated communication. Live faces and voices can make remote interaction feel more socially immediate.
Audio codec: An audio codec encodes and decodes digital audio, sometimes compressing it for storage or transmission. Speech must be compressed and delivered alongside video.
Microphone: A transducer that converts sound waves into an electrical or digital signal. It captures speech for transmission.
Television: A system for transmitting and displaying moving images, often with synchronized sound. Videotelephony adapted television technology for two-way communication.
Telemedicine: The delivery of health services at a distance using communications technologies. Clinicians use video calls for consultations and follow-up care.
Digital divide: Unequal access to digital technologies, connectivity, and the skills needed to use them. Poor connectivity or device access can exclude people from video communication.

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TelephonyBroader topic: It extends telephone-style conversation by adding live video.