The Salesforce B2C architecture runs on three highly scalable platforms: Salesforce, Commerce, and Marketing.
Connectors enable the connectivity that allows cross-cloud actions required to support sophisticated use cases such as handling abandoned carts and personalized marketing recommendations. Connectors useful to retail include Marketing Connector, Marketing Cloud Connect, Service Connector, Distributed Marketing, Social Customer Service, and Heroku Connect.
Various key use cases can be implemented by using Connectors and APIs.
For additional detail, review the solution architecture diagrams and information included in the Customer 360 Guide for Retail.