Block diagram

The schematic diagram of a radio does not show the width of each connection in the printed circuit board, but the layout does.

[4] Geometric shapes are often used in the diagram to aid interpretation and clarify meaning of the process or model.

They are also a valuable source of concept building and educationally beneficial in non-engineering disciplines.

[5][6] In process control, block diagrams are a visual language for describing actions in a complex system in which blocks are black boxes that represent mathematical or logical operations that occur in sequence from left to right and top to bottom, but not the physical entities, such as processors or relays, that perform those operations.

It is possible to create such block diagrams and implement their functionality with specialized programmable logic controller (PLC) programming languages.