What is BPMN?

Business Process Model and Notation (BPMN) is an internationally recognised standard (ISO 19510) maintained by the Object Management Group (OMG). It gives business analysts and developers a shared visual language for describing workflows — from a simple approval flow to a multi-department order-fulfilment pipeline.

Because BPMN diagrams are backed by a well-defined XML schema, a diagram is not just documentation: it is an executable specification. Engines such as Fleans parse that XML and run the process exactly as drawn.

The four symbol families

Every BPMN diagram is built from just four categories of symbols.

Family	Shape	Purpose	Examples
Events	Circle	Something that happens — starts, interrupts, or ends a process	Start Event, Timer, Message, End Event
Activities	Rounded rectangle	A unit of work the engine executes	Script Task, User Task, Call Activity, Sub-Process
Gateways	Diamond	A routing decision that splits or merges the flow	Exclusive (XOR), Parallel (AND), Inclusive (OR)
Flows	Arrow	Connects the above elements in sequence	Sequence Flow, Message Flow

A minimal example

Below is the simplest possible BPMN process — a start event, one task, and an end event connected by sequence flows:

  (O)  ──▶  [ Review request ]  ──▶  (O)
 start            task                end

In practice you layer in gateways for branching, intermediate events for waiting on timers or messages, and sub-processes for encapsulating reusable logic.

Where to go next

BPMN Support — see which BPMN elements Fleans implements today and how to use them.
OMG BPMN 2.0 Specification — the full standard if you want every detail.