A circuit diagram (also known as a schematic) is a simplified conventional graphical representation of a circuit.
A pictorial circuit diagram uses simple images of components, while a schematic diagram shows the components of the circuit as simplified standard symbols; both types show the connections between the devices, including power and signal connections. Arrangement of the components interconnections on the diagram does not correspond to their physical locations in the finished device.
Unlike a block diagram or layout diagram, a circuit diagram shows the actual connections being used. The diagram does not show the physical arrangement of components.
They are used for Electrical, Mechanical, Electronic, Pneumatic, Hydrolic , plumming and such like.
