The Graphics Glossary

Block (Function) Diagram

A Block Diagram is a specialized, high-level flowchart used in engineering. It utilizes a structured form to present a high-level overview of major system components, key process participants and relationships with internal and external interfaces.

Block Diagram

Typical Uses

A Block Diagram is used to describe and improve existing systems and to design new systems. It provides a quick, high-level view of the work and rapidly identifies points of interest in the process. Because of its high-level perspective, it may not offer the level of detail required for more comprehensive planning or analysis. Team members who construct a Block Diagram must have a clear understanding of how the system operates.

Best Practices
  • Identify the process. Determine the process to be illustrated. Define the start point and finish point.
  • Identify the key process participants. Identify all key individuals or work groups that participate in the process.
  • Create and label the diagram. Add a symbol for each component of the system, connecting them with arrows to indicate flow. Also, label each symbol so that it is easily identified.
  • Indicate input and output. Label the input that activates the process, and label that output that ends the process.
  • Verify accuracy. Consult with all stakeholders to verify accuracy.