| Admin |
| License |
| Licensed_Plugin | Extends the Plugin interface to add additional functions for licensed plugins. |
| Plugin | Basic interface implemented by all Barn2 plugins. |
| Plugin_Activation_Listener | Something which listens for plugin activation or deactivation events. |
| Premium_Plugin | Extends Simple_Plugin to add additional functions for premium plugins (i.e. with a license key). |
| Simple_Plugin | Basic implementation of the Plugin interface which stores core data about a WordPress plugin (ID, version number, etc). Data is passed as an array on construction. |