Gerber file: It is a file in ASCII vector format used for transferring PCB fabrication data from a computer aided design (CAD) or electronic design automation (EDA) software tool to PCB manufacturers. Gerber data is the universal format used in the PCB manufacturing industry and encapsulates the printed circuit board design data required by manufactures including drill, legend, copper layers, soldermask data. The Extended Gerber format (RS-274-X) was preceded by the now obsolete Standard Gerber format (RS-274-D).