CAD file formats

• CAD is an image file format used by AutoCAD. AutoCAD was created by AutoDesk, and creates 2-D and 3-D designs.
• CAD files hold information for these images, as well as drafting information. CAD stands for Computer Aided Design.
• There are several CAD file formats are: DWG, DXF, DGN, STL, DWF.

DWG

• A DWG file is a database of 2D or 3D drawings created with AutoCAD, a professional CAD program.
• It contains vector image data and metadata that describes the contents of the file.

DXF

• A DXF file is a data file saved in a format developed by Autodesk and used for CAD vector image files, such as AutoCAD documents.
• DXF files are similar to .DWG files, but are more compatible with other programs since they are ASCII (text) based.

DGN

• 2D/3D drawing format used by MicroStation construction design software.
• Based on either the Intergraph Standard File Format (ISFF) or the newer V8 DGN standard.
• Can be converted to the more universal .DWG format by AutoCAD LDT. The DGN extension is short for "design."

STL

• Design format used for stereolithography, a rapid prototyping technology used for producing three-dimensional parts; contains a 3D design used as a master model for creating numerous prototypes.

DWF

• 2D/3D drawing format developed by Autodesk as a device independent and resolution independent drawing format for distributing designs.
• Saved in a compressed format, which reduces file size; may contain design data, graphics, and text.