Flash Video, or FLV, is a container file format used to deliver video via the Adobe Flash player. Deployed by leading video sites such as YouTube, Yahoo! Video, and many others, Flash Video is an open format which supports H.264, VP6 and Sorenson Spark formats.
The QuickTime (.mov) file format functions as a multimedia container file that supports the most popular video and audio codecs, and stores audio, video, effects, and text data (for subtitles). The QuickTime file is a unique container format with its ability to support an encoded media stream or a data reference to a media stream located in another file.