What is SAP Integration Suite?
It's SAP's own integration platform as a service, for building and running integration flows between SAP and other systems, SAP's own or otherwise, through a flow-based designer and a library of prebuilt content packages.
Is SAP Integration Suite the same as SAP PI/PO?
No, though it's the successor to it. PI/PO (Process Integration/Process Orchestration) was SAP's older, on-premise middleware. Integration Suite is the cloud-based platform SAP is moving customers toward as PI/PO support winds down.
How do I integrate Salesforce with SAP?
Either through SAP Integration Suite's prebuilt Salesforce content, if you're already running or planning to run it for other integrations, or through a direct build against SAP's API and Salesforce's own API, which is usually the faster, lighter path for a single connection.
Does every business running SAP need Integration Suite?
No. It makes the most sense once you're managing several integration flows at once and want one platform handling monitoring and error recovery across all of them. A business with a single integration need often gets a faster, cheaper result from a direct build.
What is MM-FI or FI-SD integration in SAP?
That's a different kind of integration than connecting SAP to an outside system: it refers to how SAP's own internal modules, Materials Management, Financial Accounting, Sales and Distribution, are configured to post to each other automatically, a goods receipt updating inventory and triggering an accounting entry, for example. It's configuration work inside SAP itself, not something an external integration platform touches.