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.

Why AutoCAD

AutoCAD ushered in the transition from
really expensive mainframe and minicomputer CAD systems costing tens of
thousands of dollars to merely somewhat expensive microcomputer CAD programs
costing a few thousand dollars.
AutoCAD’s 3D abilities have grown by leaps and bounds over the last several
releases, and 3D modeling is becoming a common way of checking designs
before they’re drafted. Nevertheless, AutoCAD is, first and foremost, a program
for creating two-dimensional technical drawings: drawings in which
measurements and precision are important because these kinds of drawings often get used to build something. The drawings you create with AutoCAD
must adhere to standards established long ago for hand-drafted drawings.
The up-front investment to use AutoCAD is certainly more expensive than the
investment needed to use pencil and paper, and the learning curve is much
steeper, too. So why bother? The key reasons for using AutoCAD rather than
pencil and paper are
✓ Precision: Creating lines, circles, and other shapes of the exact dimensions
is easier with AutoCAD than with pencils.
✓ Modifiability: Drawings are much easier to modify on the computer
screen than on paper. CAD modifications are a lot cleaner, too.
✓ Efficiency: Creating many kinds of drawings is faster with a CAD program
— especially drawings that involve repetition, such as floor plans
in a multistory building. But that efficiency takes skill and practice. If
you’re an accomplished pencil-and-paper drafter, don’t expect CAD to
be faster at first!
Figure 1-1 shows several kinds of drawings in AutoCAD 2011

Why choose AutoCAD? AutoCAD is just the starting point of a whole industry
of software products designed to work with AutoCAD. Autodesk has helped
this process along immensely by designing a series of programming interfaces
to AutoCAD (but not, alas, to AutoCAD LT — see the “Seeing the LT” section
later in the posts) that other companies — and Autodesk itself — have used
to extend the application. Some of the add-on products have become such
winners that Autodesk acquired them and incorporated them into its own
products. When you compare all the resources — including the add-ons, extensions,
training courses, books, and so on — AutoCAD doesn’t have much PC
CAD competition.

Introducing AutoCAD and AutoCAD LT

Maybe you’re one of the few remaining holdouts who continue to practice
the ancient art of manual drafting with pencil and vellum. If so,
I must tell you, you’re a dwindling breed. Or maybe you’re completely new
to drafting and yearn for the wealth and fame (would I lead you on?) of the
drafter’s life. Maybe you’re an engineer or architect who needs to catch up
with the young CAD hotshots in your office. Maybe you tried to use AutoCAD
a long time ago, but gave up in frustration or just got rusty. Or maybe you
currently use an older release, such as AutoCAD 2006 or even (if you’re into
antiques) AutoCAD 2000.
Whatever your current situation or motivation, I hope that you enjoy the
process of becoming proficient with AutoCAD. Drawing with AutoCAD is challenging
at first, but it’s a challenge worth meeting. AutoCAD rewards those
who think creatively about their work and look for ways to do it better. You
can always find out more, discover a new trick, or improve the efficiency and
quality of your drawing production.
AutoCAD first hit the bricks in the early 1980s, around the same time as the
first IBM PCs. It was offered for a bewildering variety of operating systems,
including CP/M (ask your granddad about that one!), various flavors of UNIX,
and even Apple’s Macintosh. By far the most popular of those early versions
was for MS-DOS (your dad can tell you about that one). Eventually, Autodesk
settled on Microsoft Windows as the sole operating system for AutoCAD.

AutoCAD 2011 and AutoCAD LT 2011 are supported in the following Windows
flavors, including both 32- and 64-bit versions:
✓ Windows 7 and Windows Vista Home Premium
✓ Windows 7 Professional
✓ Windows 7 and Windows Vista Enterprise
✓ Windows 7 and Windows Vista Ultimate
✓ Windows Vista Business
✓ Windows XP Professional
✓ Windows XP Home (32-bit only)
Although it’s not officially supported, it can also run in Windows XP Tablet
2005 Edition and make use of the tablet functionality included in Windows
Vista and Windows 7. Trying to do production drafting on a tablet isn’t a
great idea due to limitations in the graphics system, but I know it works,
because I’m running it that way myself!
Because of AutoCAD’s MS-DOS heritage and its emphasis on efficiency for
production drafters, it’s not the easiest program to master, but it has gotten
easier and more consistent over the past decade or so. AutoCAD is pretty
well integrated into the Windows environment now, but you still bump into
some vestiges of its MS-DOS legacy — especially the command line (that
text area lurking at the bottom of the AutoCAD screen. But even the command line — oops! command window — is kinder
and gentler in AutoCAD 2011.