The player is licensed under a Creative Commons License. It allows you to use, modify and redistribute the script, but only for noncommercial purposes. For corporate use, please apply for a commercial license.
The easiest way to get to know the player is by using the setup wizard. Select an example, set the file or playlist you want to play and copy-paste the embed code to your site. If you want to play Youtube content in the player, you also have to copy the yt.swf file along with the player.swf.
The JW Player Wiki contains a wealth of information about the player, including:
The source code of all different versions of the player can be found here. You can click a version and download the ZIP files (the small links at the bottom!).
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