As I mentioned earlier lessons CodeIgniter have more predefined libraries. These will optimize the additional configurations if any in your application needed. Syntax: [php] $this->load->library('name of library'); $this->load->library('email'); [/php] If you want send any email by through your application, you have to just configure the all the configuration values in 'email' config. Then whenever you want send any email you just have to load the email library. We have other libraries too in CodeIgniter like 'form_validation' for validating the form at server side, 'pagination' class for paging, 'table' class to create table and etc. [php] $this->load->library('form_validation'); $this->load->library('pagination'); $this->load->library(table'); [/php]