The key difference between require() and include() is that if you require() a file that can't be loaded (eg if it isn't there) then it generates a fatal error which will halt the execution of the page completely, and no more output will be generated. On the other hand, if you include() a file that can't be loaded, then this will merely generate a warning and continue building the page =================================== GET: Parameters remain in browser history because they are part of the URL Can be bookmarked. GET method should not be used when sending passwords or other sensitive information. 7607 character maximum size. Url example: page2.php?category=sport POST: Parameters are not saved in browser history. Can not be bookmarked. POST method used when sending passwords or other sensitive information. 8 Mb max size for the POST method. Url example: page2.php