add_action($tag, $function_to_add, $priority, $accepted_args);
add_filter($tag, $function_to_add, $priority, $accepted_args);
The $tag parameter is where you specify the hook you want to add to; $function_to_add is the name of your function. The next two are optional, but worth knowing about: $priority is used to determine the order in which your action ought to occur, relative to other actions that might be happening on the same hookâlarger numbers happen later. $accepted_args
And to remove them (notice you have to do this indirectly):
function remove_some_filter() {
remove_filter(tag, function, priority, args);
}
add_action('init', 'remove_some_filter')
Example:
add_action('wp_head', 'wicked_favicon')
This runs everytime the page head is constructed, you can have the specific function inside functions.php:
function wicked_favicon() {
echo '<link rel="shortcut icon" href="'
. get_bloginfo('stylesheet_directory')
. '/images/favicon.ico"/>';
}