tutorial
http://www.anaesthetist.com/mnm/javascript/index.htm
http://www.nczonline.net/blog/2009/12/15/writing-maintainable-code/
http://www.nczonline.net/blog/2009/06/09/computer-science-in-javascript-binary-search-tree-part-1/
https://developer.mozilla.org/en/JavaScript
editable section
http://jsfiddle.net/mekwall/XNkDx/
graphics