For example, a block diagram of a radio isn't expected to show each and every connection and dial up and switch, however, the schematic diagram is. The schematic diagram of a radio doesn't show the diameter of each link from the circuit board, but the layout diagram will not.
In electrical engineering, a design may often begin as a rather high level block structure, getting increasingly more detailed block diagrams because the design progresses, finally finishing in block diagrams detailed enough that every individual block is readily executed (at that point the block diagram will be also a schematic diagram). This is known as top down design.  Geometric shapes are frequently utilised from the diagram to aid interpretation and describe meaning of the procedure or version. The geometric shapes are linked by lines to signify institution and direction/order of traversal. Each engineering field has their own significance for every form. Block diagrams are used in every discipline of technology. They're also a valuable source of concept building and educationally valuable in non-engineering areas.
Block diagrams rely on the principle of this black box in which the contents are concealed from view either to avoid being distracted by the details because the details are not known. We know what goes in, we know what happens, but we can not see how the box does its own work.
In process control, block diagrams are a visual language for describing actions within a complex system in which cubes are black boxes which represent mathematical or logical operations that happen in sequence from left to right and top to base, although not the physical things, such as chips or radiators, that perform these operations. It is likely to create such block diagrams and execute their functionality with technical programmable logic control (PLC) programming languages.
Block diagrams are generally used for higher level, less detailed descriptions which are meant to describe overall concepts without issue for the specifics of implementation. Compare this with the schematic diagrams and design diagrams used in electrical engineering, which reveal the implementation details of electrical parts and physical construction.
In biology there is a growing use of technology fundamentals, techniques of research and ways of diagramming. There's some similarity between the block structure and what is called Systems Biology Graphical Notation. Since it is there's use created in systems biology of the cube structure technique harnessed by control technology where the latter itself is an application of control theory.
A block diagram is a diagram of a system in which the main parts or works are represented by blocks joined by lines which show the relationships of the cubes.
A good instance of this is that the function block diagram, one of five programming languages found in part 3 of this IEC 61131 (view IEC 61131-3) standard that is quite formalized (see formal method ), with stringent rules for how diagrams should be assembled. Directed lines are used to link input factors to block input signal, and block presses to output variables and inputs from different cubes.
To create an analogy to the map creating planet, a block diagram is very similar to a highway map of an whole nation. The major towns (functions) are listed but the minor county roads and city roads aren't. After troubleshooting, this elevated level map is useful in narrowing down and isolating in which a problem or error is.