What's the exact thread URL?

I have a thread in the BST section which has the following URL -

http://forums.digitalpoint.com/showthread.php?t=1135797

I also found this URL -

http://forums.digitalpoint.com/showthread.php?p=10253175

(from a guy who gave me an iTrader)

which looks similar to my above thread url. Which one is right?
What does the 'p' and 't' mean within these URLs? Please do suggest.

 

Actual thread URL is: http://forums.digitalpoint.com/showthread.php?t=1135797

His post URL is: http://forums.digitalpoint.com/showpost.php?p=10253175&postcount=5

It would make sense that (t) is thread and (p) is post. He probably used his post URL but took out the &postcount=5, that's all.