License: MIT and GPL licenses
Home Page: http://www.jstree.com/
Author: Ivan Bozhanov
It is packaged as a jQuery plugin.
jsTree is absolutely free (licensed same as jQuery – under the terms of either the MIT License or the GNU General Public License (GPL) Version 2).
<link rel="stylesheet" type="text/css" href="jstree/themes/default/style.css" />