.flv File — Flash Video

FLV (Flash Video) is a container format that was synonymous with online video during the web's formative years, from roughly 2005 to 2015. Developed by Macromedia (later Adobe), FLV stored video encoded with Sorenson Spark or VP6 codecs (and later H.264) alongside MP3 or AAC audio. Flash Video powered YouTube, Hulu, Vimeo, and virtually every video-sharing site during this period, delivered through the Flash Player browser plugin. The format supported progressive download and streaming through RTMP (Real-Time Messaging Protocol), enabling both on-demand and live video delivery. FLV files included metadata for seeking, resolution, frame rate, and duration. The decline of Flash Video began with Apple's 2010 decision to exclude Flash from iOS and accelerated as HTML5 video with MP4/WebM gained browser support. Adobe discontinued Flash Player in December 2020. While FLV files are no longer created for web delivery, vast archives exist from the Flash era. Legacy FLV content can be played with VLC and converted to modern formats using FFmpeg or HandBrake.