Q: Hide widgets/plugins from dashboard I have two plugins in the dashboard, SEO Wordpress and Custom Content Type Manager, and for security reasons I want to hide these from dashboard. How to do that?
I tried to hide the SEO Wordpress with this:
// Remove Admin Dashboard menus
 function wp_admin_dashboard_remove_menus() {
     global $menu;
     $restricted = array(('Comments'), __('Users'), __('Updates'), __('wpseo_dashboard'));
     end ($menu);
     while (prev($menu)){
         $value = explode(' ',$menu[key($menu)][0]);
         if(in_array($value[0] != NULL?$value[0]:"" , $restricted)){
             unset($menu[key($menu)]);
         }
     }
 }

 add_action('admin_menu', 'wp_admin_dashboard_remove_menus');

Tried many combinations like:
__('wpseo')
__('wp-seo')
__('wp_seo')

But the SEO menu did not hide.

A: Wordpress SEO
If you want to remove the admin menu:

you can do that with:
function hide_wpseo() {
       remove_action('admin_menu', 'zeo_options_menu');
}
add_action( 'init', 'hide_wpseo');

where it will be removed for all users.
WordPress SEO by Yoast
To hide the admin menu: 

and the admin menu bar:

one can use:
function hide_yoastseo() {
    remove_action('admin_bar_menu', 'wpseo_admin_bar_menu',95);
    remove_menu_page('wpseo_dashboard');
}
add_action( 'admin_init', 'hide_yoastseo');

where it will be hidden for all users.
Custom Content Type Manager
Here one can hide the admin menu:

from all users with:
function hide_cctm() {
    remove_menu_page('cctm');
}
add_action('admin_init', 'hide_cctm');


A: Do you want to hide it for a specific kind of user like an author? If so, you can use the Advanced Access Manager plugin http://wordpress.org/extend/plugins/advanced-access-manager/
With this plugin you can decide what the user(group) has access to in the backend and also what permissions he/she has. 

A: For removing plugin's menu from multisite dashboard
foreach($GLOBALS[ 'menu' ] as $key => $value) {

    remove_menu_page($value[2]);

}

For adding menu use add_menu_page();
