GstarCAD is a highly-functional alternative to AutoCAD that makes an admirable attempt to take on a well-established and prohibitively expensive competitor.
GstarCAD works in much the same way as other computer assisted drawing software - as well as providing many of the same tools and features, it also supports a large variety of file formats. As well as the standard .DWG and .DXF, GstarCAD allows you to use more than 10 other formats in your work.
Even though it's not a very original approach, it does mean that anyone who has worked or trained on the original should have no problem using GstarCAD. Pair that with the program's good help and online tutorials, and it really does become a viable alternative.
GstarCAD is a very solid alternative to other, more famous computer assisted drawing programs.