copying files...?

I want to copy a file from a users PC (via a form) to a specific folder on the webserver and store the file name in the Database. I have tried to use the copy($string, $path) function but I keep getting errors. Does anyone know a simplat solution for this? Do I have to copy the contents of the file to a temp file on the server first? If so how? Or is there another function to do what I require? thanks, Andrew