Title says my entire question. I think I saw someone forward domain.com to example.com/subfolder and have spent about a week trying to figure out how to best do this..
My goal is to have user type in domain.com?id=cow and go to example.com/subfolder/index.php?id=cow, yet still see domain.com?id=cow in the address bar.
I've messed with masking, DNS, looked a little into htcaccess (i've done very very little in htcaccess) I'm really at a loss as to what to type into google to find what i'm trying to do, any guidance would be appreciated!

http://domain.com/?id=cowto show the content ofhttp://example.com/subfolder/index.php?id=cowand option two is (since it's PHP) to actually get the contents of the (remote?) website and render it where you want it (use cURL or file_get_contents or something). – ionFish Jan 4 at 3:20