An entity relationship diagram (ERD), one instance of a block diagram, represents an information system by demonstrating the relationships between people, objects, locations, concepts or events within that system. (See a picture over the ERD definition site.)
Block diagrams are used in a scientific context. In the study of biology, for instance, block diagrams can be utilised to exhibit biological functions and interrelations.
Block diagrams are a generalized representation of a theory and aren't meant to display full information in regards to manufacture or design. Contrary to schematics, blueprints and design diagrams, block diagrams do not portray the essential detail for physical construction. Block diagrams are created simple so as to not cloud theories.
The simplification in block diagrams can also be useful when demonstrating an idea, but concealing the inner workings of possibly key intellectual property (IP). Top-down design in electrical technology frequently progresses through increasingly detailed block diagrams. Block diagrams in process control reveal the functions of surgeries but not the components that play them. The functions of block diagrams can then be executed using programmable logic controls (PLC).
Block diagrams are used in engineering and design of diagrams such as software, hardware, electronics and procedures. Most commonly, they signify concepts and systems at a greater level, less thorough overview. The diagrams are useful for troubleshooting technical problems.