When inserting a Flash Video file in your page, you can also insert code to detect whether the user has the correct version of the Flash Player to view the Flash Video. If they don’t have the correct version, they will be prompted to download the latest version of Flash Player.
A different version of Flash Player may be needed to view a Flash Video depending on the codec used to create the video. If your video was created with the Sorenson Squeeze codec, site visitors will need Flash Player 7 or later to play progressive download video, and they’ll need Flash Player 6.0.79 or later to play streaming video. If your video was created with the On2 codec, site visitors will need Flash Player 8 or later.