What is a flowchart?

Process flowcharts—also known as process maps—are a visual representation of complex processes that make them more accessible. Project managers use flowcharts as templates to streamline workflows for the teams they oversee. Industrial engineers use them to illustrate the workings of intricate facilities. Software developers create flowcharts to plan the logical steps in the computer software and algorithms they create.

With as many types of flowcharts as there are use cases for them, flowcharts are an essential document in nearly every sector. People use flowcharts to visualize, design and document a countless range of processes and procedures.

A flowchart can aid in any of these tasks:

• Documenting a process or procedure

• Brainstorming ideas

• Business process management (BPM) and business process analysis (BPA)

• Increasing clarity and improving communication between colleagues and teams

• Outlining a decision-making procedure

• Clarifying the reporting structure of an organization

• Optimizing a process or workflow

• Explaining how a process is done

Though all flowcharts follow the same basic format, different types of flowcharts are tailored to specific contexts. The following flowchart examples are some of the more common flowchart types in use today.

• Program flowcharts are the blueprints for software and computer programs, establishing the logical structure they follow. Before beginning the coding process, programmers might create program flowcharts to establish an overall understanding of how the program will work. Engineers can refer to program flowcharts when analyzing and debugging programs.

• System flowcharts govern the fundamental sequence of events in a system—anything from food preparation in a restaurant kitchen to disaster response protocols to customer retention measures on an e-commerce platform.

• Workflow diagrams detail the process for initiating and completing a business process. They aid teams and organizations in understanding which personnel are responsible for which portions of a business process and are useful in project management for optimizing workflows and eliminating bottlenecks. When compared to data-driven process models, workflow process maps are more subjective and qualitative.

• Decision flowcharts illustrate the stages and outcomes of a decision-making process. An initial decision leads to multiple subsequent choices until the process concludes in one of several results. Decision flowcharts are also known as decision trees due to the branching nature of their flowchart shape.

• Data flow diagrams (DFD) chart the flow of information through a process, network or system. Data flowcharts are best applied to static systems such as customer order intake processes and can struggle to represent the real-time data streams created by data engineers.

• Process flow diagrams (PFD) illustrate the operations of chemical and process engineering facilities. Industrial engineers can consult PFDs to learn how the primary pieces of equipment in a plant relate to each other, create training documents and optimize procedures across facilities.

• Swimlane diagrams indicate the personnel responsible for each stage of a workflow. Drawing inspiration from the lanes in a swimming pool, swimlane charts arrange the steps of the workflow into separate rows or columns for each relevant team member, team or department. Since they often illustrate organization-wide procedures, swimlane flowcharts are also known as cross-functional flowcharts.

• Organizational charts—typically referred to as org charts—display the internal structure of a team, department or organization. The most senior members or stakeholders are placed at the top of the chart, with branches extending downward through the group's reporting hierarchy.

Industrial engineers Frank and Lillian Gilbreth first introduced the concept of flowcharts to the American Society of Mechanical Engineers (ASME) in 1921 with their Flow Process Chart. Their presentation, entitled Process Charts: First Steps in Finding the One Best Way to Do Work, laid the groundwork for the role of flowcharts in workflow optimization.

Throughout the 1930s and 1940s, other engineers further honed the concept of the flowchart and improved its efficacy as a tool. In 1947, the ASME released a standardized set of common flowchart symbols based on the Gilbreths’ original work.

The 1990s saw the arrival of Unified Modeling Language (UML) activity diagrams—digital flowcharts created with specialized UML-based flowchart software. UML was created in the 1990s to standardize common flowchart symbols.

In 2005, the Business Process Management Initiative (BPMI) codified the concept of business process modeling and notation (BPMN). This common modeling language visually depicts business processes to remove the ambiguities of textual descriptions. Today, online flowchart makers such as Lucidchart and Miro are widely available and include flowchart templates to streamline the creation process.