Learn CODEIGNITER with Real Code Examples

CodeIgniter follows the MVC (Model-View-Controller) design pattern, separating application logic, presentation, and data management.

It is lightweight and optimized for performance, making it suitable for shared hosting environments.

Provides built-in libraries for database abstraction, session management, form validation, and security.

Minimal configuration is required to get started, allowing developers to focus on building features rather than setup.

CodeIgniter supports RESTful API development, CRUD operations, and integration with third-party libraries.

MVC framework - clean separation of concerns

Database abstraction layer - simplifies CRUD operations

Form validation and security helpers

Session and cookie management

RESTful API support and routing flexibility

Controller - handles user requests and application logic

Model - interacts with the database and represents data

View - renders HTML or JSON output to the user

Helpers - utility functions for common tasks

Libraries - reusable classes providing additional features

application/ - contains MVC components, config, and libraries

system/ - core framework files

public/ - publicly accessible assets

writable/ - cache, logs, and session storage

tests/ - unit and integration tests

Define routes in `application/config/routes.php`

Create controllers to handle application logic

Create models for database interaction

Build views for user interface or API response

Test application in a browser or via API clients

Beginner: Simple web pages with dynamic content

Intermediate: CRUD web application with user authentication

Advanced: RESTful API with token-based authentication

Expert: Modular application with multiple environments

Architect: Enterprise application integrating multiple services

CodeIgniter vs Laravel: Lightweight vs full-featured

CodeIgniter vs Symfony: Simple setup vs enterprise-grade

CodeIgniter vs CakePHP: Minimal vs convention-heavy

CodeIgniter vs Slim: Full MVC vs micro-framework

CodeIgniter vs Yii: Quick prototyping vs advanced features

2006 - CodeIgniter 1.0 released by EllisLab

2008 - CodeIgniter 2.0 introduced MVC improvements

2015 - CodeIgniter 3.0 released with modern PHP support

2019 - CodeIgniter 4.0 released with full Composer support

2023–2025 - Continued bug fixes, security patches, and community contributions

Controller - handles requests and logic

Model - interacts with database

View - renders output

Helper - utility functions

Library - reusable class functionality