Printed Circuit Boards (PCB's) and Small Scale Integrated Circuits (SSIC) were manually traced buy an operator, usually a draftsman or electronic engineer then plotted on a large pen plotter (In later years to faster Electrostatic Plotters) to be visually inspected to confirm that the physical layout properly matched the schematic. Once the layout and schematics final edits were manually checked to confirm their accuracy, the multiple layers of the physical circuitry were sent to a film plotter to create masks for fabrication.