Computer-Aided Drafting and Design, also known as CADD, is the creation of drawings using a computer program rather than a pen, triangle, square and protractor.  Back when I started in CADD in the early 1960s, it took a very large room full of computers to draw even a simple circle or geometric shape, and the software cost millions of dollars.  Only universities and the biggest companies used CADD back then, and no one could imagine that just a few decades later there would be tens of millions of people creating CADD drawings at home and work.

Although there were many companies that had the idea that CADD would be a real killer application, it was a small company called Autodesk that really revolutionized the industry.  In 1980, a group of 13 programmers met in northern California, and decided to create a computer "automated desk."  This desk would have drawers to store information, a calendar to schedule meetings, a telephone to communicate with other computers, and an automated "Etch-A-Sketch" for making drawings.  In fact, this desk would have been the first graphical user interface (GUI) -- if they had succeeded.  However, the group, which called themselves "Autodesk," couldn't find anyone who was particularly interested in a GUI back in those very first days of the IBM Personal Computer.  Remember those 8088 processors with 64 KB of RAM?

So they decided to concentrate on the drawing portion, mostly because they could use it to quickly lay out their programming logic diagrams.  In late 1981, this group attended the very first Computer Dealers Exposition (COMDEX) in Las Vegas, and was rather astonished to find that thousands of people wanted to buy their drawing software (this is back when a successful program might sell 500 copies), which they had named "AutoCAD." So all of a sudden, AutoCAD was in high demand, and Autodesk was in business.

As AutoCAD has been called "one of the most revolutionary computer products in history," just what did AutoCAD really do to enhance industrial processes?  Let's take a quick look at how the design process works, both manually and with AutoCAD.

Al the Architect has this great idea for a building pop up while he's slurping down dim sum in Chinatown, so he grabs the nearest piece of paper (probably the proverbial napkin), and starts sketching out his new masterpiece.  Al has just started what is called a "conceptual design."  When he gets back to his office, Al grabs a few other people and refines his overall look-and-feel of the building, working on what will be his "preliminary design."  Once he finds someone who likes his idea, and is willing to fork over a few million for construction, Al will create his "detailed design," which will include construction drawings, details of the walls, roof, windows, and a few hundred other things.  Part of this design process is getting a structural engineer to take Al's design and see if it will really stand up if there's a hurricane, or someone runs into the side of the building.  Another part is having roofers design the roof, masons design the facade, electricians design the wiring, and so on.  You can see that building design is a very complex process!

All of these design tasks have one thing in common: they're all done using drawings.  And another common element is that each of the hundreds or thousands of drawings will be changed, modified, and mangled over and over again as the architect, construction company, engineers, contractors, and the owner decide that there's a new and better way to build this masterpiece.  Here is where AutoCAD becomes especially valuable.

Once a drawing is created manually, it is reviewed and red-lined by a whole chain of people.  Once enough red lines have appeared, the drawing is completely redrawn.  Let's say that it took the drafter 8 hours to create the first drawing; when the changes are incorporated, it will take him another 8 hours to manually redraw it.  With AutoCAD, it may take that drafter the same 8 hours to create the original drawing, but only 30 minutes to make all of the changes!  When you consider that the average architectural drawing is changed approximately 50 times in the course of design, you can quickly see that using AutoCAD can save hundreds of drafting hours and thousands of dollars.  Multiply that by the millions of projects worldwide, and you're starting to save some real money!

But the advantages don't end there.  AutoCAD allows you to create "libraries" of details that are used and reused; when a drafter inserts a detail (like a window or door), he is saving perhaps an hour of time, as well as standardizing on something that has already been identified as applicable on other projects.  When the roofer needs to make a change to ensure that the roof stays up, he can do it electronically in AutoCAD, and everyone else on the project can immediately see what changes have been made.