CodeIgniter 3 and CodeIgniter 4 are two major versions of the CodeIgniter PHP framework, each with its own set of improvements and differences.

Here are some of the key differences between CodeIgniter 3 and CodeIgniter 4:

PHP Version: CodeIgniter 3 supports PHP version 5.2.4 or newer, while CodeIgniter 4 requires PHP 7.2 or later, taking advantage of newer PHP features and improvements.

Namespace Support: CodeIgniter 3 doesn’t use namespaces extensively, whereas CodeIgniter 4 embraces namespaces for improved code organization, autoloading, and separation of concerns.

PSR Standards: CodeIgniter 4 follows PSR-4 autoloading standards for classes and PSR-1/PSR-2 coding standards, enhancing interoperability and making it easier to integrate with other frameworks and libraries that adhere to these standards.

Routing: CodeIgniter 4 introduces improved routing features, providing better flexibility and control over the routing system compared to CodeIgniter 3.

Model-View-Controller (MVC) Features: CodeIgniter 4 offers enhancements to its Model-View-Controller architecture, including improvements in the model and view layers, allowing for more modern and efficient application development.

CLI Support: CodeIgniter 4 includes enhanced command-line interface (CLI) tools, making it easier to perform various tasks like migration, seeding, etc., through the terminal.

Database Handling: CodeIgniter 4 improves its database handling, supporting features like Query Builder improvements, Query Caching, and better database migration tools.

Improved Security: While CodeIgniter 3 has various security features, CodeIgniter 4 puts a stronger emphasis on security by default, providing built-in features like cross-site request forgery (CSRF) protection, better encryption libraries, etc.

Documentation and Community: As a newer version, CodeIgniter 4 has continued to improve its documentation and support, benefiting from an active and growing community compared to CodeIgniter 3.

Backward Compatibility: CodeIgniter 4 is not fully backward compatible with CodeIgniter 3 due to significant changes, so migrating applications from 3 to 4 might require code adjustments and updates.

These are some of the notable differences between CodeIgniter 3 and CodeIgniter 4. When choosing between them, consider factors such as required PHP version, desired features, compatibility, and community support for your project needs.

codeigniter #developers