To make an analogy to the map creating world, a block structure is similar to a highway map of an entire nation. The major towns (functions) are listed but the minor county roads and city roads are not. When troubleshooting, this elevated level map is helpful in narrowing down and isolating where a problem or malfunction is.
In biology there is a growing use of engineering principles, techniques of investigation and ways of diagramming. There is a similarity between the block diagram and what's called Systems Biology Graphical Notation. As it is there's use made in systems economics of the block structure technique exploited by controller technology in which the latter itself is an application of control theory.
A block diagram is a type of a system where the main parts or works are represented by blocks linked by lines that show the connections of the cubes. They're heavily utilised in engineering in hardware design, digital design, software design, and process flow diagrams.
In process control, block diagrams are a visual vocabulary for describing activities in a intricate system in which blocks are black boxes which represent mathematical or logical operations that occur in order from left to right and top to base, although not the physical entities, such as processors or relays, that perform these operations. It is possible to make such cube diagrams and execute their performance with specialized programmable logic control (PLC) programming languages. )
Block diagrams are generally used for higher degree, less comprehensive descriptions that are meant to describe overall concepts without consideration for the details of implementation. Contrast this with the design diagrams and design diagrams used in electrical technology, which show the implementation details of electrical elements and physical structure.
In electrical engineering, a design will often start as a quite significant level block structure, getting more and more detailed block diagrams as the design develops, eventually ending in block diagrams comprehensive enough that each individual block can be easily implemented (at that stage the block structure can be also a schematic diagram). This is known as top down design.  Geometric shapes are frequently used from the diagram to help interpretation and describe meaning of this process or version. The geometric shapes are connected by lines to signify institution and direction/order of traversal. Each engineering field has their own significance for each form. Block diagrams are employed in each discipline of technology. They are also a valuable source of concept building and educationally beneficial in non-engineering areas.
A good example of that is that the function block structure, one of five programming languages described in section 3 of this IEC 61131 (see IEC 61131-3) standard that is quite formalized (see proper system), with stringent rules for the diagrams are to be assembled. Directed lines have been utilized to link input factors to block input signal, and prevent presses to output variables and inputs from other blocks.
Block diagrams rely upon 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 understand what happens, we all know what happens, but we can't see how the box does its own work.
For example, a block diagram of a wireless is not expected to demonstrate each and every link and dial and change, however, the design diagram is. The design of a wireless doesn't show the diameter of each link from the printed circuit board, but the layout diagram does.