of which conform to the Defense Department's MIL-D-28000 Engineering Drawings Subset of IGES) use the entities that they describe, e.g., the illustration of the LEADER (ARROW) ENTITY (Type 214) can be used as a test case for translator implementers, because it contains all 12 arrow head styles defined by the standard. These WYSIWYG example files can be distinguished by a leading "F" and trailing "X" in the file name (like f214x.igs), and this library is called the IGES X-files by members of the IGES community. Here is one of the example figures, Figure 2 from Appendix A (fmeparte.igs), that has appeared in every version of IGES since Version 3.0. It uses linear, angular, and ordinate dimension entities, as well as examples of both circular and conic arcs. It is usually the first part used when testing an IGES translator, because the standard has a picture of what it should look like. See also ISO 10303-21 References Notes 1982 https://books.google.com/books/about/Digital_representation_for_communication.html?id=5LDgAAAAMAAJ 1990 https://books.google.com/books/about/Digital_representation_for_communication.html?id=tyFZAAAAYAAJ . Baseline version was January 12, 1999. . Baseline version was January 5, 1998. External links CAD file formats Computer file formats Computer-aided design software Graphics file formats