What Is CAD? Computer-Aided Design, Simply Explained

Look around you. Your chair, your pencil, your shoes and your tablet were all designed by somebody. And almost all of them were designed on a computer, using something called CAD.

In this post you will learn what CAD is, who uses it, and how you're already doing it when you build in Kids 3D Lab.

What does CAD stand for?

CAD stands for Computer-Aided Design. That means designing things with the help of a computer.

• Computer — the machine you use.
• Aided — helped.
• Design — planning how something will look and work.

So CAD is using a computer to help you plan and draw things before they are made.

Before computers

Long ago, designers drew everything by hand, on big sheets of paper. They used rulers, pencils and special triangles. If they made a mistake, they had to rub it out, or start again!

Drawing a car by hand could take weeks. And a drawing is flat. You can't turn it around to look at the back.

What CAD can do

CAD changed everything. With CAD you can:

• Build in 3D. Turn your model around and look at it from every side.
• Use exact sizes. Type 56 mm, and it's exactly 56 mm. No wobbly lines!
• Change things quickly. Make it wider with one number. Undo a mistake with one click.
• Test before you make. Check that parts fit together, or that a model fits a printer.
• Share it. Send the file to a friend, a factory or a 3D printer.

Who uses CAD?

Lots of people use CAD in their jobs:

When you build in Kids 3D Lab, you're doing the same kind of work, just with easier buttons!

How CAD works in Kids 3D Lab

Grown-up CAD programs and Kids 3D Lab share the same big ideas:

1. Building from shapes

Most things are made from simple shapes. A car is boxes and cylinders. A snowman is balls. In CAD you start with shapes and put them together.

2. Exact sizes

Every number in Kids 3D Lab is in millimetres. When you type a size, it's a real size, just like in the CAD tools engineers use.

3. Adding and taking away

You can add shapes together, and you can take away shapes using holes. Engineers do the same thing. A cup is a cylinder with a smaller cylinder taken away.

4. Checking before making

Before printing, Kids 3D Lab checks your model: does it fit? Is anything floating? Is it all one piece? Engineers check their designs before they're made too, because mistakes in a factory are expensive!

From CAD to a real thing

A CAD model is a plan. To make it real, you need a machine. For small things at home or school, that's often a 3D printer.

1. You design the model in CAD.
2. You save it as a file, like an STL or a 3MF.
3. A slicer app cuts the model into thin layers.
4. The 3D printer builds it, one layer at a time.

Read What Is 3D Printing? to learn how printers work.

Some words CAD designers use

Try it yourself

You can start doing CAD right now:

1. Open Kids 3D Lab and click New build.
2. Add a Cylinder. Make it 40 wide and 4 tall. That's a medal!
3. Add a Star. Make it 28 wide and 2 tall. Put it on top of the cylinder.
4. Add a Tube for the loop, so a ribbon can go through.
5. Click Export and check it's ready to print.

Congratulations. You're a CAD designer!

Questions kids ask

What is CAD used for?

CAD is used to design almost everything that gets made: cars, phones, buildings, bridges, furniture, toys, shoes and even teeth braces. Designers use it to plan exact sizes, check that parts fit, test ideas on screen and send the design to a machine or a 3D printer.

What does CAD do?

CAD lets you build a model of something on a computer before you make it. It keeps every size exact, lets you change your design in seconds, shows it from every side, and saves it as a file a machine can make.

Is CAD hard?

Big CAD programs have lots of buttons, so they take time to learn. But the ideas are simple: shapes, sizes, adding and taking away. Start with an easy app, and you'll learn the ideas first.

What CAD programs do grown-ups use?

There are many, like Fusion, SolidWorks, FreeCAD and Onshape. Each one is made for different jobs. You don't need them to start. Kids 3D Lab teaches the same ideas.

Can CAD make anything?

CAD can design almost anything. Making it is another step. Some things are too big, too small or too tricky for a home printer, but factories can make them.

How old do you have to be to use CAD?

You can start at about 5 with a grown-up, using simple tools. Many engineers say they started by building with blocks and drawing as kids.

What does CAD stand for in DT?

At school, DT means Design and Technology. In DT, CAD still means computer-aided design: drawing and planning a product on a computer before you make it. You may also hear CAM, which means computer-aided manufacture. That's when a machine, like a 3D printer or a laser cutter, makes the thing you designed. Doing GCSE Design and Technology? Read CAD in DT: A Student's Guide.

What is 3D CAD?

Some CAD is flat, like a plan of a house drawn from above. That is 2D CAD. 3D CAD makes models with width, depth and height, that you can turn round and look at from every side. A 3D printer needs a 3D CAD model to print. Everything you build in Kids 3D Lab is 3D CAD.

Is there CAD for kids?

Yes! Kids 3D Lab is CAD made for kids, from about 5 years old. It's free, it works in a web browser, and it needs no account. You build with shapes, every size is in real millimetres, and you can print what you make. It's a great first step before the CAD programs grown-ups use. Read more in CAD for Kids.

For grown-ups

CAD is one of the most useful skills a child can start early, because it combines maths, art and problem solving. The key ideas, like combining shapes, subtracting and working to exact dimensions, transfer directly to professional tools later on. Encourage your child to design things that solve small problems at home, then test them. For a gentle start, try Make Your First 3D Model in 10 Minutes.

Start doing CAD →