Difference between SAP BPC and SAP PCM

Hello experts,

I would like to know what are the differences between SAP BPC and SAP PCM?

There this discussion on the topic but it does not tell me much:

BPC vs PCM

Is there someone that can highlight the in which case they are used as both tools seem to offer the same functionalities in terms of forecasting.

Thank you very much in advance.

Kind regards,

Chanthy