Are you sure it loads libraries more than once? I would have thought the OS would do copy-on-write (at least, that's what Linux does with shared objects; IIRC Windows doesn't support copy-on-write).
I meant PHP libraries in source form. Have you ever used an MVC framework in PHP? It usually starts with including lots of PHP files at the start. These files need to be loaded and code in them run to initialize the framework (e.g. read config files, initialize request mappings, open database connections, etc.). All this is done *per request* while in Java it is done once per deployment.
A PHP script is parsed and executed every time a script is requested.
That means that every request, every file you include (such as the php-based framework libraries) have to be loaded into memory.
Runtime in PHP is the time it takes to run one single script, not an entire user session.
PHP does offer a native cache system now (the APC), but that is not on by default.
Thanks everyone for helping, i want to learn making simple webpages
i have little knowledge of HTML and just know how to make things display on a webpage using PHP..
do you people think i should first learn HTML thoroughly and then PHP..
or just start with JAVA?