video

Video is the representation of moving visual images, often accompanied by synchronized audio, that can be captured, stored, transmitted, and displayed by electronic devices. The term covers both the process of recording moving images and the resulting footage that viewers watch on screens. In common usage, video contrasts with film, which historically refers to images recorded on photographic film; video implies electronic sensors, digital processing, and often non-linear editing.

Historically, video emerged through mechanical and later electronic systems in the 20th century, with analog broadcasting and videotape becoming widespread mid-century. Digital video rose with advances in data storage, compression, and online distribution from the late 20th century onward. Today, video is delivered via broadcast, optical discs, local storage, and streaming over networks, with high-definition and ultra-high-definition formats commonly used in consumer and professional contexts.

Video data is typically stored in containers such as MP4, MKV, AVI, and MOV, and encoded with codecs including MPEG-2, H.264/AVC, H.265/HEVC, VP9, and AV1. Parameters such as resolution, frame rate, bit depth, and color space affect quality and bandwidth requirements. Common resolutions include 720p, 1080p, 4K (2160p), and higher, with typical frame rates of 24, 30, and 60 frames per second.

Uses span entertainment, education, surveillance, telecommunication, and video conferencing. Editing and compression enable flexible post-production and efficient distribution. Accessibility features like subtitles and captions improve inclusivity, while legal and technical considerations involve copyright, licensing of codecs, and adherence to relevant standards.