AutoCAD has been around a long time — since 1982, which I suspect, dear readers, is longer than some of you! 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 is, first and foremost, a program for creating 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

Figure 1-1 shows several kinds of drawings in AutoCAD 2010.

Figure 1-1. Cities, houses, little toy trains — what do you want to draw today?

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 chapter) 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.

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:

Table 1-1 shows which versions (described later in this chapter) use which DWG file formats.

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 2000 — or even older.

AutoCAD LT is one of the best deals around, a shining example of the old 80/20 rule: roughly 80 percent of the capabilities of AutoCAD for roughly 20 percent of the money. (Actually, with recent price creep, it's now more like a 70/30 rule!) Like AutoCAD, AutoCAD LT runs on mainstream Windows computers and doesn't require any additional hardware devices. With AutoCAD LT, you can be a player in the world of AutoCAD, the world's leading CAD program, for a comparatively low starting cost.

AutoCAD LT is a very close cousin to AutoCAD. Autodesk creates AutoCAD LT by starting with the AutoCAD program, taking out a few features to justify charging a lower price, and adding a couple of features to enhance ease of use versus full AutoCAD. As a result, AutoCAD LT looks and works much like AutoCAD. The drawing areas, Ribbons, and Application Menu of the two programs are nearly identical. (LT is missing a few Ribbon tabs, panels, and commands.)

In fact, the major difference between the programs has nothing to do with the programs themselves. The major difference is that AutoCAD LT lacks support for several customization and programming languages that are used to develop AutoCAD add-ons. So almost none of the add-on programs or utilities offered by Autodesk and others are available to LT users.

AutoCAD LT also has only limited 3D support. You can view and edit 3D objects in AutoCAD LT, so you can work with drawings created in AutoCAD that contain 3D objects. However, you can't create true 3D objects in LT.

The lack of 3D object creation in LT isn't as big a drawback for many users as you may think. Despite a lot of hype from the computer press and CAD vendors (including Autodesk), 3D CAD remains a relatively specialized activity. The majority of people use CAD programs to create 2D drawings.

Although you may hear claims that AutoCAD LT is easier to master and use than AutoCAD, the truth is that they're about equally difficult (or easy, depending on your NQ [nerd quotient]). The LT learning curve doesn't differ significantly from that of AutoCAD. AutoCAD was originally designed for maximum power and then modified somewhat to improve ease of use. AutoCAD LT shares this same heritage.

Fortunately, the minimal differences between LT and AutoCAD mean that after you've climbed that learning curve, you'll have the same great view. You'll have almost the full range of the AutoCAD 2D drafting tools, and you'll be able to exchange DWG files with AutoCAD users without data loss.

There's been a new release of AutoCAD every spring since AutoCAD 2004 was launched in 2003. That's not much time for even an army of programmers to deliver a compelling new feature set that's going to convince all users that they just have to upgrade. What seems to have been happening is a concentration on particular areas in recent releases. For example, AutoCAD 2007 was the 3D release; the 3D modeling engine was made much easier to use, but there was relatively little to please the 2D crowd. By contrast, AutoCAD 2008 was deemed to be "the drafter's release" because of the number of enhancements to 2D drawing capabilities — above all, the introduction of annotative documentation objects. In AutoCAD 2009, the new Microsoft Office 2007-style interface got the lion's share of development time; significant new features were limited to some 3D navigation tools.