A gateway is used to model concurrency in a process. It is used to control the flow of execution, or in BPMN 2.0 terminology, the tokens of execution.
A gateway is capable of consuming or generating tokens. It is graphically visualized as a diamond shape, with an icon inside. The icon describes the type of gateway. Gateways are described in detail in the Activiti user guide.
- Parallel gateways: Models a fork into multiple paths of execution, or a join of multiple incoming paths of execution.
- Exclusive gateways: Also known as an XOR gateway, this is used to model a decision in a process definition.