how can stick background

hello there well I wana stick my background image just like this one
http://demo.9themestore.com/nts_kgalaxi ... orum/index

can any one help me to sort it out.

Bajwha

You need to set background position to fixed, please look at this article http://davidwalsh.name/css-fixed-position-background-image in David Walsh blog, everything is explained there.