' A Gerber File is a standard file format used by printed circuit board (PCB) fabrication houses that contains information necessary for computer controlled machines to draw exact patterns for circuit boards. These patterns are typically used to assemble and electrically connect electronics assemblies. The patterns usually contain features such as land patterns, signal traces, drilled holes, milling and cutting information. The Gerber Format is originally a subset of EIA RS-274-D. Later the format was then extended by the so called "Mass Parameters" and was then also called RS-274-X. ' from Wikipedia Gerber File

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