The Importance of Being DWG

To take full advantage of AutoCAD in your work environment, you need to be
aware of the DWG file format, the format in which AutoCAD saves drawings.
Here are some DWG facts to keep in mind:
✓ In some cases, an older release of AutoCAD can’t open a DWG file that’s
been saved by a newer AutoCAD release.
✓ A newer release of AutoCAD can always open files saved by older
versions.
✓ Some previous AutoCAD releases can open files saved by the subsequent
one or two versions. For example, AutoCAD 2007 and AutoCAD
2008 can open DWG files saved by AutoCAD 2009. That’s because
Autodesk didn’t change the DWG file format between those releases.
However, the drawing file format did change with AutoCAD 2010, so
drawings created in the current release must be saved in an older
format to be openable in AutoCAD 2009 and earlier.
✓ You can use the Save As option in newer releases to save the file to
some older DWG formats. In fact, AutoCAD 2011 can save as far back as
AutoCAD Release 14, which dates all the way back to 1997!
The new file format in AutoCAD 2010 was necessary to handle new features —
especially parametric drafting. The new format is also more efficient at saving
files and can handle much larger objects. Best of all from the user’s perspective,
it’s noticeably faster to work with than AutoCAD 2009.
Working with AutoCAD is easier when your coworkers and colleagues in
other companies all use the same release of AutoCAD and AutoCAD-related
tools. That way, your DWG files, add-on tools, and even the details of your
CAD knowledge can be mixed and matched among your workgroup and partners.
In the real world, you may work with people, probably from other companies,
who use AutoCAD releases as old as AutoCAD 2006 — or even older.
Many programs claim to be DWG compatible — that is, capable of converting
data to and from AutoCAD’s DWG format. But achieving this compatibility is a
difficult thing to do well. Even a small error in file conversion can have results
ranging in severity from annoying to appalling. Every time you open a drawing
file, AutoCAD checks its parentage and warns you if the drawing was created
by a non-Autodesk program. If you exchange DWG files with people who use
other CAD programs, you may have to spend time finding and fixing translation
problems.