What are the Gerber and Gerber 274x files?
They are ASCII files with coordinates and simple instructions that allow us to interpret the printed circuit board to be manufactured with independency of the design CAD system used.
The different shapes that appear in the printed circuit board (circles, rectangles, oblongs, etc.) and the correspondent diameter are identified with the name “Dcodes” (D10, D15…). Each Dcode has one or more coordinates assigned.
At first, the definition of the diameters and shapes of the Dcodes came in a file a part, therefore the Gerber 274x file, which is a developed version of the Gerber, has the advantage of including in one single file the diameter rand the shape definition of each Dcode together with the coordinates.
The result is the visualization of the wanted image, that will match with the original in the CAD .
Definitively, it is preferable to use the Gerber274x output because we have all the information we need in one single file and, therefore, the mistake at the moment of translating to other formats is minimum.