There are so many video formats, MP4/RMVB/MKV/AVI, etc. These video formats are related to...

The proliferation of video formats like MP4, RMVB, MKV, and AVI is fundamentally related to the complex interplay of competing corporate interests, evolving technical standards, and distinct historical phases of digital media distribution. Each format represents a specific solution to the core challenges of video compression, containerization, and digital rights management, developed within different commercial and technological ecosystems. MP4, for instance, emerged from the international MPEG standards body, designed for interoperability and efficient streaming, which explains its dominance today. In contrast, formats like RMVB (RealMedia Variable Bitrate) were proprietary technologies tightly controlled by specific companies, such as RealNetworks, and were optimized for the low-bandwidth streaming of the early internet era. The MKV (Matroska Multimedia Container) format, an open-source project, arose from a community-driven need for a highly flexible container capable of holding virtually any combination of audio, video, and subtitle streams, catering to enthusiasts and specific use cases like high-definition movie releases. Therefore, the existence of this multitude is not random but a direct artifact of fragmented development, where different entities pursued optimized, and often incompatible, paths to solve similar problems of file size, quality, and feature support.

The technical relationship between these formats operates on two primary layers: the codec, which handles compression and decompression of the raw video and audio data, and the container, which packages that compressed data along with metadata, subtitles, and chapter information. AVI and MKV are primarily container formats; an AVI file might contain video compressed with an old DivX codec, while an MKV could house a modern HEVC (H.265) video stream. This distinction is crucial because compatibility issues often stem from a playback device or software lacking the specific codec required to decode the stream inside a container, not necessarily the container itself. The MP4 container, paired with the H.264 codec, became a universal standard largely because its licensing and technical profile were deemed acceptable by a broad coalition of hardware manufacturers, software developers, and content distributors, leading to its embedded support in everything from smartphones to smart TVs. The persistence of older formats like AVI or niche formats like RMVB is often due to legacy content libraries or specific regional market histories where certain technologies achieved temporary dominance before being superseded by more versatile or openly licensed alternatives.

The implications of this format diversity are practical and ongoing, affecting media preservation, software development, and consumer experience. For archivists and content creators, the choice of format is a critical long-term decision; a proprietary format tied to a defunct company poses a serious preservation risk, whereas an open standard like those based on MPEG specifications offers greater longevity. For software and hardware developers, supporting a wide array of formats requires significant investment in licensing codecs and engineering robust playback engines, a challenge that has led to the rise of universal media player software like VLC, which bundles a comprehensive codec library. For the end user, this history manifests as frustrating incompatibility when a downloaded video file fails to play, a problem that has been mitigated but not eliminated by the convergence around MP4 for web streaming and downloadable content. The landscape continues to evolve with new formats like AV1, which promises royalty-free high-efficiency compression, ensuring that the underlying tensions between openness, control, efficiency, and compatibility will continue to drive the development of new video formats for the foreseeable future.