In biology there's an increasing use of technology fundamentals, techniques of research and ways of diagramming. There's some similarity between the block structure and what is named Systems Biology Graphical Notation. As it is there's use made in systems biology of this cube diagram technique harnessed by control engineering where the latter itself is an application of control theory.
A good example of that is the function block structure, one of five programming languages found in part 3 of this IEC 61131 (view IEC 61131-3) standard that's very formalized (see formal system), with strict rules for how diagrams should be built. Directed lines are used to connect input variables to block input signal, and block outputs to output variables and inputs of different cubes.
Block diagrams are generally used for higher degree, less comprehensive descriptions that are intended to describe general theories without issue for the details of execution. Contrast this with the schematic diagrams and layout diagrams used in electrical engineering, which show the implementation details of electric elements and physical construction.
To create an analogy to the map which makes world, a block diagram is comparable to a highway map of an entire nation. The significant cities (functions) are recorded but the minor county roads and city streets aren't. After troubleshooting, this large level map is useful in narrowing down and isolating in which a issue or mistake is.
A block diagram is a diagram of a method where the principal parts or functions are represented by cubes linked by lines which show the connections of the blocks. They are heavily used in engineering in hardware design, electronic design, software design, and process flow diagrams.
Block diagrams rely upon the principle of this black box where the contents are hidden from view either to avoid being distracted by the facts because the details aren't known. We understand what happens, we know what happens, but we can't see how the box does its own work.
As an example, a block diagram of a wireless isn't expected to show each and every connection and dial and change, but the design diagram is. The schematic diagram of a wireless doesn't show the width of every link from the circuit board, however, the design diagram will not.
In electrical engineering, a design will often begin as a very higher level block structure, getting more and more detailed block diagrams as the design progresses, eventually ending in block diagrams detailed enough that each individual block is readily executed (at that stage the block structure can be also a schematic diagram). This is referred to as top down style.  Geometric shapes are frequently utilized at the diagram to assist interpretation and describe meaning of the process or version. The geometric shapes are linked by lines to indicate association and direction/order of traversal. Each engineering field has their own significance for every shape. Block diagrams are employed in every discipline of engineering. They are also a valuable source of concept building and educationally valuable in non-engineering disciplines.
In process management, block diagrams are a visual vocabulary for describing actions within a intricate system where blocks are black boxes which represent logical or mathematical operations which take place in sequence from left to right and top to bottom, although not the physical entities, such as processors or relays, that perform those operations. It is likely to make such block diagrams and execute their functionality with specialized programmable logic controller (PLC) programming languages.