A Start Event refers to a marker in BPMN, which means start of a process.
In BPMN, the event that influences the order or timing of the business process is classified into three types: Start, Intermediate, and End. Among these types, the start event shows the place where a process starts. In some cases, two or more start events exist in the same process level. When the end event is used, at least one start event is required.
In a sequence flow, flow of a process starts with a start event. The start event has no input sequence flow. In some cases, it is a target of a message flow and it has an input message. However, the start event cannot be the source of a message flow. In a word, it never has any output message.
The start event is drawn with a simple line circle. The cause of the event ("Trigger") is identified by the marker in the circle. The markers and triggers are shown in the following table.
- KATO, Masato “An introduction to Business Process Modeling by BPMN”, Soft Research Center, 2006. (Japanese) ISBN:978-4-88373-226-5
- Associated with Business Process Modeling Notation (BPMN) 1.1 (2008).