By default Codeigniter URL may look like http://www.example.com/index.php/controller/method.
To change this to seo friendly like http://www.example.com/controller/method we have to do some changes in .htaccess.
1.Create .htaccess file in the root and place the below code
RewriteEngine On RewriteCond %{REQUEST_FILENAME} !-f RewriteCond %{REQUEST_FILENAME} !-d RewriteRule ^(.*)$ index.php/$1 [L]
2.Dont forget to enable rewrite_module in apache modules if you didnt enabled it yet.To enable it goto WAMP->Apache->Apache modules->rewrite_module
3.In the config file change index_change to empty
$config['index_page'] ="";
Also change
$config['rewrite_short_tags'] = TRUE;