Windows Media Video (WMV) is a file type which can contain video in one of several video compression formats developed by Microsoft. The original video compression format used in the file, also known as WMV, was originally designed for Internet streaming applications, as a competitor to Real Video. The other compression formats, such as WMV Screen and WMV Image, cater for specialized content. Through standardization from the Society of Motion Picture and Television Engineers (SMPTE), WMV9 has gained adoption for physical-delivery formats such as HD DVD and Blu-ray Disc. Though sometimes used interchangeably, note the distinction between Windows Media, the file type, and Windows Media Video, the video compression format. Windows Media the file type is a container (in the Advanced Systems Format) which can contain video in one of several different video compression format, only one of which is the Windows Media Video video compression format, alongside audio in an audio coding format.
Flash Video is a container file format used to deliver video over the Internet using Adobe Flash Player version 6 and newer. Flash Video content may also be embedded within SWF files. There are two different video file formats known as Flash Video: FLV and F4V. The audio and video data within FLV files are encoded in the same manner as they are within SWF files. The F4V file format is based on the ISO base media file format and is starting with Flash Player 9 update 3. Both formats are supported in Adobe Flash Player and developed by Adobe Systems. FLV was originally developed by Macromedia. Flash Video is the de facto standard for web-based streaming video (over RTMP). Notable users of it include YouTube, Hulu, VEVO, Yahoo! Video, metacafe, Reuters.com, and many other news providers.