DXF

DXF stands for Drawing Exchange Format (or Drawing Interchange Format) and was created by AutoDesk for their AutoCAD and AutoDRAW CAD systems.

There are ASCII (plain text) and binary variants, since AutoCAD Release 10, of DXF. The ASCII variant is apparently more prominent. Both ASCII and Binary versions can be identified using the same tag as the DWG format. Binary DXF is not to be confused with DXB, a related but distinct format.

Identification
Binary DXF files begin with the ASCII signature " ".

ASCII DXF files usually begin with, followed by " ".

Software

 * LibreOffice
 * Konvertor

Sample files

 * http://cd.textfiles.com/amigaenv/DXF/OBJEKTE/ ...
 * https://telparia.com/fileFormatSamples/image/dxf/

Resources

 * Wikipedia page on DXF
 * AutoDesk DXF Reference
 * AutoCAD Release 12 DXF Reference
 * , from the Encyclopedia of Graphics File Formats
 * Official AutoDesk specifications for each version of AutoCAD (13 and higher), for example this from AutoCAD 2008
 * Minimum Requirements for Creating a DXF File of a 3D Model (textfiles.com; Sept 1993 version)
 * Drawing Interchange and File Formats Release 12 (from Autodesk, 1992)