creating&using json file

https://github.com/mbostock/d3

http://stackoverflow.com/questions/6396623/jquery-getjson-access-control-allow-origin-issue

//Origin null is not allowed by Access-Control-Allow-Origin

http://blog.jhoney.net/411

http://www.slideshare.net/mehmetakin/ajax-world

//ajax

http://brain.dailyon.net/?paged=11

http://winflahed.tistory.com/62