Interpreting output of backward hook

Thank you again @ptrblck for your explanations. Sorry, the inputs and outputs that you mentioned means input activations to this module and the output activations of this module? And the parameter that you also mentioned means weights and bias of this module? Am I right? Because, based on the code snippet provided by @albanD in this discussion How do hooks work?, the register_hook function is registered on the output activations of the module.

Thank you so much.