PHP is a widely-used general-purpose scripting language that is especially suited for Web development and can be embedded into HTML. Much of its syntax is borrowed from C, Java and Perl with a couple of unique PHP-specific features thrown in. The goal of the language is to allow web developers to write dynamically generated pages quickly. It is a project of the Apache Software Foundation.
PHP 4.4.2 ChangeLog | PHP 5.1.2 ChangeLog

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