A Call Activity identifies a point in a process where a global process is used. The Call Activity acts as a wrapper for the invocation of the global process within the execution. The activation of the Call Activity results in the transfer of control to the called global process.
A Call Activity shares the same notation as a Task or SubProcess with a thick line around the boundary of its shape.
The BPMN2 Call Activity corresponds to the Reusable SubProcess of BPMN 1.2, and the BPMN2 SubProcess corresponds to the Embedded SubProcess of BPMN 1.2.