I have scripts written for PHP 4. They work fine in a PHP5 environment but I am curious to know what PHP5 has to offer to make scripts faster and more efficient. Does using static methods, adding private public functions, etc help improve the actual performance of the script?
Object oriented features will be slower than procedural. You make up with that on how much easier it is to manage the program. Now is the performance difference that big? No not really but it's worth noting anyways. If you're already using objects and things like that then having private and publc functions can help make it easier to manage the program.