What is the difference between a pool and a thread in BPMN?

In BPMN, a pool represents the main participant in the process — usually an organization or system that performs the process. A pool defines the scope and separates one process from another.

A lane is a subdivision within a pool used to divide roles, departments, or functions within a single organization. It helps structure the process and shows who is responsible for what.

Simply put:

• Pool is an external container for the process, often reflecting a separate organization or system.
• Lane is an internal division within a pool to distribute responsibilities among roles or departments.