CodeIgniter provides a rich set of libraries. It is an essential part of CodeIgniter as it increases the developing speed of an application. It is located in the system/library.

It can be loaded as follows,

$this->load->library(‘class_name’);

In CodeIgniter, libraries are collections of classes and functions that provide specific functionality which can be reused throughout your application. These libraries facilitate common tasks such as form validation, database manipulation, file uploading, etc.

To load a library in CodeIgniter, you typically follow these steps:

Autoloading (Optional): If you want a library to be automatically loaded on every page request, you can specify it in the application/config/autoload.php file.

php

$autoload['libraries'] = array('library_name');

Replace 'library_name' with the name of the library you want to autoload.
Manual Loading (Preferred in Most Cases): Alternatively, you can load libraries manually within your controllers or other parts of your application where needed.

php

$this->load->library('library_name');

Replace 'library_name' with the name of the library you want to load.

Here’s a breakdown of what happens:

$this->load refers to CodeIgniter’s loader class.
library() is a method provided by the loader class for loading libraries.
'library_name' is the name of the library you want to load.

For instance, if you want to load the Form Validation library, you would use:

php

$this->load->library('form_validation');

Once loaded, you can then utilize the functions and classes provided by the library throughout your application. It’s important to note that CodeIgniter follows a naming convention where the name of the library file should be the same as the name of the library class. For example, if you’re loading the Form Validation library, the library file should be named Form_validation.php, located in the application/libraries directory.