CodeIgniter is a small but powerful PHP framework. As a simple and "elegant" toolkit, it can build fully functional Web applications for PHP programmers. If you are a developer using shared hosting and struggling with client deadlines, if you are tired of those clunky frameworks
Who is CodeIgniter for? CodeIgniter is what you need if... You want a compact frame. You need great performance. You need broad compatibility with various PHP versions and configurations on standard hosts (e.g. PHP4). You want a framework that requires almost zero configuration. You want a framework that doesn't require using the command line. You want a framework that doesn't have to adhere to restrictive coding rules. You are not interested in large-scale integration libraries like PEAR. You don't want to be forced to learn a template language (although you can choose the template parser you require). You don't like complexity and love simplicity. You need clear, complete documentation.
The main changes in CodeIgniter from 1.7.3 to 2.0 are: PHP 4 is no longer supported, and the minimum requirement now is PHP 5.1. Form helper functions have built-in CSRF protection. The adapter application package scaffolding was deprecated several versions ago and has now been removed. Remove obsolete validation classes. Plugins have been removed and replaced with helper functions. Added: Route override to the main index.php file, enabling regular routes to be overridden on a per-"index" file basis. Add $route[404_override] so that 404 pages can be handled through the controller. At least 50 bugs have been fixed. The Reactor version includes all the above features, and it also has some excellent features of its own: Full query-string support. Automatically detected if base_url is empty. New cache adapter with support for filesystem, APC and memcache. Compatible with the command line to simplify the development of scheduled tasks. 20+ tweaks and improvements.
