Videos

Video refers to a sequence of visual images presented in quick succession, often with synchronized sound, to produce the perception of motion. In digital contexts, video is stored as data streams that encode both the visual frames and audio, using compression to reduce file size.

Historically, video began with analog television and film, evolving through videotape formats in the 20th century, to digital video in the late 20th and early 21st centuries. The rise of the internet enabled online video hosting and streaming, transforming how videos are distributed and consumed.

Video formats rely on codecs for compression and containers for packaging streams. Common codecs include H.264/AVC, H.265/HEVC, VP9, and AV1. Containers such as MP4, MKV, AVI, and MOV hold encoded video and audio together. Video may be progressive or interlaced; common resolutions range from standard definition to 4K and beyond, with various frame rates.

Playback and distribution occur on televisions, computers, tablets, and mobile devices, via broadcast, optical media, downloadable files, or streaming platforms. Streaming protocols like HLS and DASH enable adaptive bitrate delivery. Accessibility features include captions and audio descriptions, while metadata helps catalog and search video assets.

Applications span entertainment, education, journalism, marketing, and surveillance. Video raises considerations around copyright, licensing, privacy, and data usage. Advances in compression and streaming continue to improve efficiency and quality, shaping contemporary media consumption.