.. note:: Difference between **registration** of widgets and **implementation** of widgets: Widgets provide some functionality, e.g. collect system log errors over a time span. This functionality is provided by the implementation, a PHP class with some code. The registration is done in :file:`Services.yaml`, in order to create the actual widget with provided functionality. During registration options can be set, e.g. the time span. Registration is documented at :ref:`register-new-widget`, while implementation is documented at :ref:`implement-new-widget`.