BPMN & Process Modeling Glossary

Activity

A unit of work performed within a process. Activities can be atomic (tasks) or compound (sub-processes). They are shown as rounded rectangles in BPMN.

Ad-hoc Sub-Process

A sub-process whose inner activities have no required sequence. Participants can perform tasks in any order or skip them entirely. Shown with a tilde (~) marker.

As-Is Process

A model of how a process currently works in reality, including workarounds, inefficiencies, and informal practices. The starting point for process improvement.

Association

A dotted line connecting an artifact (text annotation, data object) to a flow element. Associations show relationships without affecting process flow.

Boundary Event

Also: Attached Event

An event attached to the border of an activity. It triggers when the condition occurs while the activity is active. Can be interrupting (cancels the activity) or non-interrupting (runs in parallel).

BPM

Business Process Management. A discipline for discovering, modeling, analyzing, measuring, improving, and automating business processes. BPMN is the standard notation used within BPM.

BPMN

Business Process Model and Notation. An ISO/OMG standard (ISO 19510) for graphically representing business processes. BPMN 2.0 is the current version, providing a rich set of symbols for modeling workflows that are both human-readable and machine-executable.

BPMN 2.0 XML

The machine-readable file format for BPMN diagrams. Unlike proprietary formats (e.g. draw.io's mxGraphModel), BPMN 2.0 XML includes both semantic process logic and visual layout, making it portable across tools.

Business Rule Task

A task that evaluates a business rule, typically using a decision engine (e.g. DMN). Shown with a table icon.

Call Activity

An activity that invokes a globally defined process or task. Unlike a sub-process, the called process is defined separately and can be reused across multiple parent processes. Shown with a thick border.

Catching Event

An event that waits for a trigger to occur before the process continues. Examples: timer catch (wait for a deadline), message catch (wait for a message).

Choreography

A type of BPMN diagram that focuses on the sequence of message exchanges between participants, rather than the internal work of any single participant.

CMMN

Case Management Model and Notation. A standard for modeling knowledge-intensive, non-routine work that doesn't follow a fixed sequence. Complements BPMN for unpredictable work.

Collaboration

A BPMN diagram showing multiple participants (pools) and the message flows between them. Collaborations model how independent organizations or systems interact.

Collapsed Pool

Also: Black-box Pool

A pool shown without internal process details -- just a horizontal bar with the participant name. Used to show that a participant exists and exchanges messages, without revealing their internal workflow.

Compensation

A mechanism for undoing completed work when a transaction fails. Compensation activities are triggered by compensation events and execute the reverse of a previously completed task.

Compensation Event

An event that triggers compensation (rollback) activities. Used in transactions to reverse completed work.

Complex Gateway

A gateway for complex branching logic that cannot be expressed with other gateway types. Requires explicit activation rules. Rarely used in practice.

Conditional Event

An event triggered when a business condition becomes true (e.g. inventory drops below threshold).

Conditional Flow

A sequence flow with a condition expression. The flow is only taken if the condition evaluates to true. Shown with a small diamond at the source end.

Continuous Improvement

An ongoing effort to improve processes incrementally. Methods include Lean, Six Sigma, and Kaizen. BPMN models serve as the baseline for measuring improvement.

Customer Journey

The complete sequence of interactions a customer has with an organization, from first awareness through purchase and support. Overlaying customer journeys on BPMN reveals where internal processes create friction.

Data Association

A dotted arrow showing how data flows into or out of an activity. Connects data objects or data stores to activities.

Data Input

Data required by a process before it can start or by an activity before it can execute. Shown as a page icon with an arrow pointing in.

Data Object

Represents information flowing through the process, such as a document, form, or dataset. Data objects can show their state (e.g. "Order [submitted]", "Invoice [approved]").

Data Output

Data produced by a process or activity upon completion. Shown as a page icon with an arrow pointing out.

Data Store

A persistent storage mechanism that exists beyond the lifecycle of a single process instance, such as a database, CRM system, or file share. Shown as a cylinder.

Default Flow

A sequence flow from an exclusive or inclusive gateway that is taken when no other condition evaluates to true. Shown with a diagonal slash mark. Prevents the process from getting stuck.

Diagram Interchange (DI)

The part of the BPMN 2.0 standard that defines how diagram layout (positions, sizes, waypoints) is stored in the XML. DI ensures that a BPMN file looks the same in any compliant tool.

Digital Transformation

The integration of digital technology into all areas of a business, fundamentally changing how it operates. Process modeling is a critical enabler -- you need to understand current processes before digitizing them.

DMN

Decision Model and Notation. A companion standard to BPMN for modeling business decisions using decision tables and logic. Often used with business rule tasks in BPMN.

End Event

Indicates where a process path ends. When all tokens in a process reach end events, the process instance is complete. Shown as a thick-bordered circle.

Error Event

An event representing a business error that disrupts normal flow. Used with sub-processes and transactions to model exception handling.

Escalation Event

An event used to escalate a situation to a higher level of responsibility. Unlike errors, escalations don't necessarily stop the current activity.

Event

Something that happens during a process. Events affect the flow and usually have a cause (trigger) or an impact (result). Shown as circles in BPMN.

Event-Based Gateway

Waits for one of several possible events (message, timer, signal) and routes to whichever event occurs first. Unlike other gateways, the decision is based on events, not data conditions.

Exception Path

Also: Unhappy Path

A branch in a process that handles errors, timeouts, or unexpected situations. Modeled with boundary events, error events, or conditional gateways.

Exclusive Gateway

Also: XOR Gateway, Decision Gateway

Routes the process down exactly one path based on conditions. Only the first matching condition fires. Think: "choose one."

Gateway

A diamond-shaped element that controls how sequence flows converge (merge) and diverge (split) within a process. Gateways determine branching logic.

Group

A visual grouping of elements for documentation or analysis purposes. Shown as a dashed rounded rectangle. Does not affect process flow or token routing.

Handoff

The point where responsibility for work transfers from one person, team, or system to another. Poorly managed handoffs are one of the most common causes of process failure.

Happy Path

The default, expected flow through a process when everything goes as planned -- no errors, no exceptions, no escalations. The main sequence from start to end.

Inclusive Gateway

Also: OR Gateway

Activates one or more paths based on conditions. Any combination of outgoing paths can fire. The join waits for all activated paths. Think: "pick any that apply."

Intermediate Event

An event that occurs between a start and end event. Can be either catching (waiting for something) or throwing (producing something). Shown as a double-bordered circle.

KPI

Key Performance Indicator. A measurable value that demonstrates how effectively a process achieves its objectives. Process models help identify where to measure KPIs.

Lane

A horizontal or vertical partition within a pool that organizes activities by role, department, or function. Lanes clarify "who does what" within a single participant. Sequence flows cross lanes freely.

Lean

A methodology focused on eliminating waste (non-value-adding activities) from processes. Often combined with BPMN to identify and remove wasteful steps.

Link Event

A pair of matching throw/catch events used as an "off-page connector" to avoid long sequence flows across a large diagram. The throw sends the token; the matching catch receives it.

Loop Activity

An activity that repeats based on a condition. Can be standard looping (repeat while condition is true) or multi-instance (execute once for each item in a collection).

Manual Task

A task performed by a person without any system assistance. Example: physically delivering a package. Shown with a hand icon.

Message Event

An event triggered by a message from another participant (pool). Used for inter-participant communication. Never used for communication within a single pool.

Message Flow

A dashed arrow showing communication between two different pools (participants). Message flows carry messages across organizational or system boundaries. Never used within a single pool.

Multi-Instance Activity

An activity that executes multiple times, once for each item in a collection. Can run in parallel or sequentially. Shown with three horizontal (parallel) or vertical (sequential) lines.

Parallel Gateway

Also: AND Gateway

Activates all outgoing paths simultaneously (split) or waits for all incoming paths to complete (join). No conditions -- all paths always fire. Think: "do everything at once."

Participant

An entity that performs a process. In BPMN, each participant is represented by a pool. A participant can be an organization, a department (in technical diagrams), a person, or a system.

Pool

A container representing a participant in a collaboration. A participant is an independent entity (organization, customer, system) with its own process. Pools define boundaries -- no sequence flows cross pool borders, only message flows.

Process

A sequence of activities, events, and gateways that together achieve a business goal. In BPMN, a process is contained within a single pool and represents the work performed by one participant.

Process Automation

Using technology to execute process steps without human intervention. Ranges from simple rule-based automation (RPA) to intelligent orchestration. BPMN models define what to automate.

Process Discovery

The practice of identifying and documenting existing processes, whether through interviews, workshops, observation, or automated mining. The first step in any BPM initiative.

Process Engine

Software that executes BPMN process models. The engine creates process instances, manages tokens, evaluates gateway conditions, and invokes tasks. Examples: Camunda, Flowable, Zeebe.

Process Instance

A single execution of a process. When a process is triggered (e.g. a new order arrives), a new instance is created. Multiple instances of the same process can run simultaneously.

Process Landscape

A high-level map showing all of an organization's processes organized by value streams, domains, or business capabilities. Provides the bird's-eye view before diving into individual process models.

Process Maturity

A measure of how well-defined, managed, measured, and optimized an organization's processes are. Common maturity models include CMMI and APQC.

Process Mining

Using event log data from IT systems to automatically discover, monitor, and improve real-world processes. Process mining reveals how processes actually execute vs. how they were designed.

Process Orchestration

Coordinating multiple services, systems, or microservices to execute a business process. A process engine reads the BPMN model and orchestrates the steps.

Process Owner

The person accountable for the performance and outcomes of a specific process. The process owner ensures the process meets its goals and authorizes changes.

Process Simulation

Running a process model with test data to predict performance, identify bottlenecks, and validate logic before deployment. Token simulation is the most common approach in BPMN.

Receive Task

A task that waits for a message from an external participant before continuing.

RPA

Robotic Process Automation. Software robots that mimic human actions in digital systems (clicking, typing, copying data). Used to automate repetitive tasks identified through process modeling.

Script Task

A task executed by a process engine using a predefined script. Used for automated calculations or data transformations.

Send Task

A task that sends a message to an external participant. Semantically equivalent to a task followed by a message throw event.

Sequence Flow

A solid arrow showing the order in which activities, events, and gateways are performed within a single pool. The primary connector in BPMN.

Service Task

A task executed by an automated service or system, such as an API call or database operation. Shown with a gear icon.

Signal Event

An event that broadcasts to all listening processes (unlike messages, which target a specific recipient). Useful for system-wide notifications.

Six Sigma

A data-driven methodology for reducing process variation and defects. Uses statistical analysis to improve process quality. DMAIC (Define, Measure, Analyze, Improve, Control) is its core framework.

SLA

Service Level Agreement. A commitment to complete a process step or deliver a service within a defined time frame. Timer events in BPMN can model SLA deadlines.

Stakeholder

Any person or group affected by or involved in a process. Effective process modeling requires engaging stakeholders to capture how work really happens.

Start Event

Indicates where a process begins. A process can have multiple start events but each instance is triggered by exactly one. Shown as a thin-bordered circle.

Sub-Process

A compound activity containing its own internal process. Can be expanded (showing details) or collapsed (hiding details). Useful for organizing complex processes into manageable chunks.

Task

An atomic activity that cannot be broken down further within the process. BPMN defines several task types: user, service, send, receive, manual, business rule, and script.

Terminate End Event

An end event that immediately terminates the entire process instance, canceling all remaining activities and tokens. Use with caution.

Text Annotation

A mechanism for adding human-readable notes and comments to a BPMN diagram. Connected to elements via associations. Does not affect process flow.

Throwing Event

An event that produces a trigger for other parts of the process or other processes. Examples: message throw (send a message), signal throw (broadcast a signal).

Timer Event

An event triggered by a time condition: a specific date, a duration, or a recurring cycle. Common use: deadlines, reminders, scheduled batch jobs.

To-Be Process

A model of how a process should work after improvement. Represents the target state. Typically created after analyzing the as-is process.

Token

A conceptual marker that moves through a BPMN process to track execution state. When a process starts, a token is created at the start event and travels along sequence flows. Gateways can split tokens (parallel) or choose paths (exclusive).

Transaction

A specialized sub-process with ACID-like properties. If any part fails, the entire transaction can be compensated (rolled back). Shown with a double border.

User Task

A task performed by a human with the assistance of a software application. Shown with a person icon. Example: "Review loan application."

Value Stream

An end-to-end sequence of activities that delivers value to a customer. Value streams operate at a higher level than individual processes and typically span multiple departments.