Sujith,
Get your friend to PM me and I'll try to help. Is his issue that he doesn't understand what shorting is? If so, then the answer is its the market term for selling something you don't already own. If gold is at 820.5 and I sell it, then if the price falls to 808 then I can buy some and give it to the guy I sold it to, keeping 12.5 dollars per ounce as profit. This only works because I don't have to deliver it at the exact instant I sell it - in the case of futures, the actual delivery might be months away. Even in the case of physical gold, if I buy and sell on the same day then the deliveries will (generally) match up.
As for 820.5 - 808 = 14.5, all I can assume is that Sujith was so excited by today's profits that his fingers slipped on the keyboard and he meant to type 12.5 for the answer!!!
Hope this helps your friend, everyone has to learn this stuff for the first time!