Function: Register a plugin’s real path.

Function: Get the filesystem directory path (with trailing slash) for the plugin __FILE__ passed in.

Function: Get the URL directory path (with trailing slash) for the plugin __FILE__ passed in.

Function: Set the activation hook for a plugin.

Function: Set the deactivation hook for a plugin.

Function: Set the uninstallation hook for a plugin.

Function: Call the ‘all’ hook, which will process the functions hooked into it.

Function: Build Unique ID for storage and retrieval.

Function: Check if any action has been registered for a hook.

Function: Removes a function from a specified action hook.