Core Service
The Core Service is a web service that allows applications to interact with Content Manager. For example, Content Manager clients such as Experience Manager and Content Manager Explorer interact with Content Manager through the Core Service, and you can use the Core Service to integrate external systems with SDL Tridion Sites. You also use the Core Service to implement Automatic Activities to control Workflow.
The Core Service is a SOAP web service based on Windows Communication Foundation. It supports WS-I Basic Profile 1.1 and more advanced WS-* protocols.