Simple questions – how do I delete all categories programatically?

For instance this returns a list of all categories

$args = array(  
    "hide_empty" => 0,
    "type"       => "post",
    "orderby"    => "name",
    "order"      => "ASC" 
);
$types = get_categories($args);

How do I simply delete them so I can replace them with other categories?