PHP5 new features
1. PHP 5 introduces the Standard PHP Library (SPL), which provides a number of ready-made classes and interfaces.
2. Access Modifiers are added in PHP5
3. PHP5 has built-in exception classes that makes it very easy to create your own customized exceptions through inheritance.
4. PHP 5 introduces the mysqli (MySQL Improved) extension with support for the features of MySQL databases versions 4.1 and higher. So use of prepare statements are allowed
5. PHP5 comes with PDO which is a common interface for different database systems is only made possible by the new object model.
6. SQLite is a database engine incorporated in php5 which can be used to develope faster, leaner and more versatile applications.
7. In PHP 5 all Extensible Markup Language (XML) support is provided by the libxml2 XML toolkit.
8. The reflection classes included in PHP 5 provide ways to introspect objects and reverse engineer code.
9. In addition to built-in classes, PHP 5 also offers built-in interfaces. Iterator is the most important, as a number of classes and interfaces are derived from this interface.
10. PHP 5 introduces a number of new “magic” methods. Magic methods begin with a double underscore, and this requires changing any user-defined methods or functions that use this naming convention.
11. The major change to PHP in version 5 relating to OOP is usually summed up by saying that objects are now passed by reference.