error($field[, $prefix = ''[, $suffix = '']])

camelize($str)

class CI_Security xss_clean($str[, $is_image = FALSE])

send_email($recipient, $subject, $message)

vars($vars[, $val = ''])

class CI_Loader library($library[, $params = NULL[, $object_name = NULL]])

set_status_header($code[, $text = ''])

If you find that no matter what you put in your URL only your default page is loading, it might be that your server does not support the REQUEST_URI variable needed to serve

form_dropdown([$name = ''[, $options = array()[, $selected = array()[, $extra = '']]]])

slash_segment($n[, $where = 'trailing'])