Each one of these strategy groups contains individual strategies. In replenishment you may, as an example, procure based on past consumption or based on future requirements. As for the planning strategies you may plan for Make to Stock or you may plan on an assembly level for Finish to Order or for the Production Scheduling Strategies you may employ takt-based, repetitive scheduling.
In either case you need to do some work so SAP can support the strategy you decided on. This work usually requires setting up some basic data. The combination of settings that support a certain strategy, I call a policy. Please note that a policy is not an SAP term. SAP didn't pre-set policies; they left it up to you to put the appropriate combination together to retain utmost flexibility. The downside to this is the fact that you need a lot of experience and detailed knowledge to figure out the right combination for the right strategy. But who said that SAP is easy? And your consultant should know how this stuff works out. (in a previous post I pointed out the necessity for a consultant who explains all the options and does NOT simply give you the solution.... you will have to flexibly adjust new solutions to changing requirements. So if the consultant gives you the solution upfront - without you understanding the dependencies - you WILL be screwed once the influencing factors vary.)
Back to policy: a policy can be described in words like :"replenish based on a automatically determined forecast model on past consumption, ordering weekly demand with a minimum of 5 pallets, rounding to a pallet size, keeping safety stock in line with growing demand and at 3 days, receiving only Tuesdays and Thursdays, sourcing with Quantity Contracts and Quota Arrangements" and then needs to be set up in SAP accordingly. In this example the setup would like something like this: