How to return some infos from a javascript with PHP+Javascript

Hi all, I need an advice from you gurus. I'm no sure about what solution to use: I have a javascript, and i'd like to be able to return some data to the server at different times. But what solutions do I have? I'm not too good at javascript and the only one i thought was to load a script in another window to pass the parameteres, like window.create("returnparameters.php?this=does&not=work")... and then close the window, but the window doesn't close under IE, and sincerely I don't like the idea to open another window! (of course I can't use the original window! :-) TIA, Duccio.