BPMN Glossary
What every BPMN 2.0 element means, with a diagram and a working TypeScript example for each.
Start Event
The trigger that begins a BPMN process instance — every process has at least one.
End Event
Marks a point where a process instance (or one of its branches) completes.
Exclusive Gateway
A decision point where exactly one of several outgoing paths is taken, based on a condition.
Parallel Gateway
Splits a process into multiple simultaneous paths that all execute, and later joins them back together.
Inclusive Gateway
Splits a process into one or more of several paths — any combination of conditions that evaluate true is taken.
Service Task
An automated step executed by a worker — code, not a human, performs the work.
User Task
A step in the process that waits for a human to complete a form or make a decision.
Sub-Process
A self-contained group of elements nested inside a parent process, used to structure or reuse logic.
Boundary Event
An event attached to a task's edge that interrupts it — commonly used for errors, timeouts, and cancellations.
Message Event
An event triggered by an incoming message — starts a process, or pauses one until a correlated message arrives.
Timer Event
An event triggered by a schedule — a fixed date, a delay, or a recurring cycle — rather than by another element completing.
Call Activity
A reference to a separately-deployed process — runs it as a child process instance, rather than embedding its steps inline.