An FLV file is a flash-compatible video file exported by the Flash Video Exporter plug-in (included with Adobe Animate) or other program with FLV file support. It consists of a short header, interleaved audio, video, and metadata packets. The file stores audio and video data in a similar format used by standard Flash (.SWF) files.
The FLV format is an open format that is also supported by non-Adobe/Macromedia programs. FLV files may be exported from QuickTime Pro or other applications that can export to the QuickTime file format.
NOTE: Animate was formerly known as Flash, which was originally developed by Macromedia but then merged with Adobe in 2005. Flash became Animate in 2016.