Business process model and notation (BPMN) diagrams tutorial

The business process model and notation (BPMN) system offers a graphic representation of your internal business processes. It shows, in flowchart form, the sequence of steps in a business process from start to finish, providing a visual aid for decision-making, collaboration, and optimization.

The graphical elements of a BPMN represent events, activities, gateways (decision points), flows and associations connecting different elements, and pools showing the participants in the process.

The BPMN modeling diagram standard defines four element types:

Flow objects

Flow objects include the following:

• Events. An event is a trigger that initiates, modifies, or finishes a flow process. Events are shown as circles containing other symbols that represent the event type. Event types include message, signal, timer, cancel, error, and others.
• Activities. An activity is a task performed within the flow process. It’s represented by a rectangle with rounded corners.
• Gateways. A gateway is a decision point, represented by a diamond shape with a symbol inside showing what type of gateway it is: inclusive, exclusive, event-based, etc.

Connecting objects

Connecting objects are shown as solid, dashed, or dotted lines that may point in one direction or another. There are three types:

• Message flow shows the direction of a message between participants in a process. Message flows are usually represented as dashed lines that end in an arrow.
• Sequence flow shows the sequential order of flow objects. Sequence flows are typically solid lines that end in an arrow.
• Association shows a connection between an artifact or text and a flow object. Association symbols are dotted lines.

Swimlanes

Swimlanes represent the space where a process occurs and show who is accountable for that process or part of the process. There are two types:

• Pools represent a process or an organization. They often appear as rectangles.
• Lanes represent individuals or teams that are part of the organization. Multiple lanes can exist within a pool or within another lane. Lanes appear as rectangles within the larger rectangle of a pool.

Artifacts

Artifacts are additional pieces of information that provide more detail when needed. There are three types defined in the BPMN model, each with its own graphical symbol.

• Data objects show what information an activity needs.
• Groups show how activities are logically grouped, independent of the flow.
• Annotations give additional explanations to parts of the flow, where needed.

A number of diagram tools support BPMN. Some of the most popular are Lucidchart, SmartDraw, Microsoft Visio (bundled with Office 365), and Draw.io.