The significant cities (functions) are listed but the small county roads and city roads are not. After troubleshooting, this high level map is useful in narrowing down and isolating in which a problem or malfunction is.
Block diagrams are generally used for higher level, less comprehensive descriptions that are intended to clarify overall concepts without difficulty for the specifics of execution. Contrast this with the schematic diagrams and layout diagrams used in electric technology, which reveal the implementation information of electrical elements and physical structure.
In process management, block diagrams are a visual language for describing actions within a intricate system in which cubes are black boxes that represent mathematical or logical operations which take place in order from left to right and top to bottom, but not the physical things, such as processors or relays, that perform those operations. It is likely to create such block diagrams and implement their performance with specialized programmable logic control (PLC) programming languages.
A block diagram is a type of a system where the principal parts or functions are represented by cubes linked by lines which show the relationships of the cubes. They're greatly utilized in engineering in hardware design, electronic design, software design, and process flow diagrams.
In electrical engineering, a style will often begin as a quite substantial level block structure, getting more and more detailed block diagrams because the design develops, finally finishing in block diagrams comprehensive enough that each individual block is readily implemented (at that stage the block diagram will be also a schematic diagram). This is referred to as top down layout.  Geometric shapes are frequently utilized in the diagram to aid interpretation and clarify meaning of this process or version. Each engineering discipline has their own meaning for every form. Block diagrams are employed in each discipline of engineering. They are also a valuable source of theory building and educationally valuable in non-engineering areas.
Block diagrams rely on the principle of the black box in which the contents are hidden from view to avoid being distracted by the facts because the details aren't known. We all understand what goes in, we all know what happens, but we can't see the way the box does its work.
A good illustration of that is that the function block diagram, among five programming languages found in section 3 of the IEC 61131 (view IEC 61131-3) benchmark that is quite formalized (see formal system), with stringent rules for the diagrams should be built. Directed lines have been used to link input variables to block inputs, and block presses to output factors and inputs from other blocks.
For example, a block diagram of a wireless isn't anticipated to demonstrate each and every connection and dial up and change, but the design diagram is. The design of a radio doesn't demonstrate the diameter of each connection in the circuit board, however the design diagram will not.
In biology there's an increasing use of technology principles, techniques of evaluation and ways of diagramming. There's some correlation between the block structure and what's called Systems Biology Graphical Notation. Since it is there's use made in systems biology of this block diagram technique exploited by controller technology in which the latter itself is an application of management theory.