How does Google treat URL with "?" as a diffrent URL

[editsha]

My question is does google treat
www.example.com and
www.example.com?sp

as a diffrent url.

if yes: then what are the things to be done to get the first url as a main url. In other words how can i exclude www.example.com?sp to be featuring in SERP

if no: then its cool;)

I have done the required settings in g-web master tools and robot.txt [selecting the Preferred domain]

Note: we use "?sp" for tracking

[Noton]

Yes Google will treat them as 2 different URLs, but Google's system is trying to merge things like this when the resulting page is the same size and content as the other, but all other search engines are not that smart, even Google often doesn't get it right.

What you want to do to solve this problem is use the Rel=Canonical tag, instruction on that tag are here:

[googlewebmastercentral.blogspot.com...]

[editsha]

hey thanks Noton ....