supply chain and value chain (Michael Porter- Corporate Strategy)

What is Starbucks supply chain and value chain (Michael Porter- Corporate Strategy) – why are processes critical to ensure organization effective and efficient performance – bring up competitive advantage (Michael Porter) opportunities.
*UPDATE*
The full assignment instructions is below, but I ONLY need help with understanding what the Michael Porter Corporate Strategy is. Hopefully this helps to clarify what Im asking for help on.
The paper needs to define business process, describe the BPM discipline, discuss what is ‘the supply chain’ in business and compare/contrast to Michael Porter business ‘value chain’. Explain how applying information technology can support and drive innovation in these core business processes (look for examples – Search internet, business journals, BPM journals . Finally select a company you are interested in learning about and chose one of their Core Supply Chain Processes from Chapter 1 in Krajewski book (Supplier Relationship Process / New Product or Service Development / Order Fulfillment / or Customer Relationship) you will be documenting and analyzing during the term.