Flowcharts translate complex procedures into a single visual language, using distinct shapes to represent specific actions and decisions. Understanding what the flowchart shapes mean is essential for anyone tasked with documenting, analyzing, or improving a workflow. Each symbol acts as a standardized icon, removing ambiguity about who is responsible for a step and what kind of step it is.
Foundational Symbols for Sequence and Direction
The most basic elements in any diagram focus on the flow of control and the progression of steps. These foundational shapes ensure the reader can trace the path from start to finish without confusion. They answer the implicit question of "what happens next" in a linear process.
The Terminal Shape
The oval or rounded rectangle serves as the bookend for the entire diagram. It signifies the start or end of a process, acting as the anchor point for all other logic. You will find the word "Start" or "End" centered within this shape, clearly marking the boundaries of the workflow.
The Process Shape
The most frequently used symbol is the simple rectangle. This shape indicates a standard process or action step, such as "Generate Report" or "Validate User Input." It tells the viewer that work is being performed or an operation is being executed within the system.
The Flow Line
Arrows, often referred to as flow lines, connect every shape together. These directed lines illustrate the sequence and direction of the workflow. They ensure the viewer follows the intended path, moving from one operation to the next without getting lost in the logic.
Decision Points and Branching Logic
Not all steps are linear; many processes require a choice based on specific conditions. This is where the diagram shifts from a simple list to a logical map of possibilities. These shapes introduce complexity but provide the necessary structure for handling exceptions.
The Decision Diamond
The rhombus (diamond) is the universal symbol for a decision point. It contains a yes/no question or a condition that evaluates to true or false. The lines exiting this shape represent the different outcomes, guiding the flow down the appropriate path based on the answer.
Advanced Representation for Data and Interfaces
As diagrams become more sophisticated, they begin to represent not just actions, but the movement and storage of information. These shapes bridge the gap between internal processes and external interactions.
The Data Shape
A parallelogram is used to indicate input or output operations. This encompasses data entering the system, such as reading a file or accepting user entry, and data leaving the system, such as writing to a database or displaying a result.
The Predefined Process Shape
A rectangle with wavy lines on the sides signifies a pre-defined function or a subroutine. This indicates that the step calls upon another part of the diagram or an external procedure. It helps keep the main diagram uncluttered by referencing complex logic defined elsewhere.
Organizational and Documentation Shapes
Standardization relies on a shared understanding of less common symbols that facilitate organization and provide context. These shapes ensure the diagram remains a reliable source of truth for stakeholders.
The On-Page Connector
When a flowchart spans multiple pages or becomes visually complex, a circle or labeled icon acts as an on-page connector. This symbol links two points together, allowing the designer to break the diagram into manageable sections while maintaining a single, continuous flow.
The Off-Page Connector
A specific variation of the connector shape features a small arc, indicating that the flow continues on a different page. This is crucial for large-scale processes, signifying that the reader should look for the matching symbol on another sheet to continue following the sequence.
