email setup

[eluser]johnmerlino[/eluser]
Now typically wouldn't the smtp host settings be in the php.ini on the server? So when I pass these configurations, what codeigniter overwrites what's on the php.ini?

I'm also a little confused by all these parameters:

Code:

'protocol' => 'smtp',
                'smtp_host' => 'secure.emailsrvr.com',
                'smtp_port' => 465,
                'smtp_user' => 'xxx',
                'smtp_pass' => 'xxx',
                'mailtype'  => 'html',
                'charset'   => 'iso-8859-1'
            )

why the need for a user name and password, when the php mail() function doesn't require it?

thanks for response