How to change the post menu and options.

function change_post_menu_label() {
global $menu;
global $submenu;
$menu[5][0] = 'Articles';
$submenu['edit.php'][5][0] = 'Articles';
$submenu['edit.php'][10][0] = 'Add New';
$submenu['edit.php'][15][0] = 'Cat';
$submenu['edit.php'][16][0] = 'Tags';
}
add_action( 'admin_menu', 'change_post_menu_label' );