This article presents the principles of the Unified Modeling Language (UML) component diagram. In the UML, a component diagram depicts how components are wired together to form larger components and or software systems. They are used to illustrate the structure of arbitrarily complex systems.
The component diagram is a very important diagram that architects will often create early in a project. However, the component diagram’s usefulness spans the life of the system. Component diagrams are invaluable because they model and document a system’s architecture. Because component diagrams document a system’s architecture, the developers and the eventual system administrators of the system find this work product-critical in helping them understand the system.