php5 v. php4

[drag0n]

I never really understood the differences betweent he two releases except for the improvements on OOP. If anybody could please help me out by maybe listing the main improvements it would be greatly appreciated. Also, if I have a intermediate-advanced php4 programmer, is there need for me to buy a new php5 book to learn it, is it as much of a jump such as VB to vb.net?
Thanks

[drew010]

Taken from the PHP news feed...

Some of the key features of PHP 5 include:

* The Zend Engine II with a new object model and dozens of new features.
* XML support has been completely redone in PHP 5, all extensions are now focused around the excellent libxml2 library (http://www.xmlsoft.org/).
* A new MySQL extension named MySQLi for developers using MySQL 4.1 and later. This new extension includes an object-oriented interface in addition to a traditional interface; as well as support for many of MySQL's new features, such as prepared statements.
* SQLite has been bundled with PHP. For more information on SQLite, please visit their website.
* A brand new built-in SOAP extension for interoperability with Web Services.
* A new SimpleXML extension for easily accessing and manipulating XML as PHP objects. It can also interface with the DOM extension and vice-versa.
* Streams have been greatly improved, including the ability to access low-level socket operations on streams.
* And lots more...

check the php5 changelog for other improvements and changes.