• CAD means computer aided design.
  • CAD is an image file format used by Autocad.
  • It is the use of computer systems to aid in the creation, analysis, modification of a design.
  • It is used to design curves and figures in 2D space; surfaces, and solids in 3D space.

2D model


3D model
  • It's software is used to increase the productivity of the designer, improve the quality of the design.
  • CAD is an important industrial art extensively used in many applications, including automotive, shipbuilding, and aerospace industries.
  • It is also widely used to produce computer animation for special effects in movies, advertising and technical manuals.
  • Its used in designing electronic systems is known as electronic design automation, in mechanical design it is known as mechanical design automation.
  • CAD software for mechanical design uses either vector-based graphics or may also produce raster graphics showing the overall appearance of designed objects. 
  • CAD file formats generally fall into one of two categories–either Native or Standards-Based.
  • Native file formats are under the control of a particular CAD software maker who can choose to change them at any time.
  • A Standards-Based format is in the hands of some standard-making organization which gets to decide when and how the format changes.
  • Some of the cad File Formats are:
     - DXF:  
  • DXF is a 2D and 3D format and technically should be viewed as a Native format. It is Autocad’s native format. But Autocad is so ubiquitous and so many CAD programs support it that DXF has come to be a pretty universal interchange format for 2D and 3D information.
     - STL:
  • STL is perhaps the universal format for pure 3D information. It is much-loved by 3D printers and somewhat loved by CAM.  The biggest problem with STL is it is just a triangular mesh. It has almost no “smarts” about the object other than its overall shape. This is fine for 3D printing where a slicer doesn’t need to manipulate the CAD data much.


      - VRML:  
  • VRML carries somewhat more information than STL, but is read by fewer software packages. 
     Examples:
  • In mechanical design
  • In electronic design