Abstract: A method for inputting data representing an engineering drawing to a computer aided design system. The method comprises the steps of creating the engineering drawing on quadrille paper or graph paper having criss-crossing lines. After creation of the drawing, the drawing is scanned by an optical reader which produces an electrical output signal representative of the drawing data. This output signal is electrically connected as an input signal to the computer aided design system. When editing the drawing, a computer generated grid pattern corresponding in scale to the criss crossing lines on the quadrille paper is superimposed on a video monitor of the computer aided design system thereby facilitating editing of the drawing on the computer aided design system.