Difference between SOP in ECC and Demand Planning in SCM

Hi Guys,

I'm been using SAP for a few months now and been on a few SAP courses such as SAP-01, TERP10 and SCM100 and have a fair understanding of how things work in ECC and SCM. However, I am struggling to get my head around the differences between SOP in ECC and DP in SCM. The main thing I want to know is what advantages does one have over the other? And why would a company decide to use DP instead of SOP or vice versa?

Any help would be much appreciated

Regards

Mark