A block diagram is a visual representation of a system which utilizes simple, labeled blocks that represent single or many objects, concepts or entities, connected with lines to show relationships between these. An entity relationship diagram (ERD), one example of a block structure, represents an information system by demonstrating the relationships between individuals, objects, locations, events or theories inside that system. (See a picture over the ERD definition webpage.)
Unlike schematics, blueprints and layout diagrams, block diagrams don't portray the necessary detail for bodily construction. Block diagrams are created simple so as not to cloud concepts.
The simplification in block diagrams may also be useful when demonstrating an idea, but hiding the inner workings of possibly key intellectual property (IP). Top-down design in electrical engineering frequently progresses through progressively detailed block diagrams. Block diagrams in process control reveal the functions of operations but not the elements that perform them. The purposes of block diagrams may then be implemented with programmable logic controls (PLC).
Block diagrams are utilized heavily in engineering and design of diagrams including electronic equipment, hardware, applications and procedures. Most frequently, they represent theories and systems at a greater degree, less detailed overview. The diagrams are helpful for troubleshooting technical problems.
Block diagrams can also be utilized in a scientific context. In the study of biology, for instance, block diagrams can be used to show biological functions and interrelations.