What defines 3D printing?

There are many different types of 3D printers, but what makes them all similar is that they build solid shapes from layers of materials, starting with an empty build area and filling it with the print. This is called additive manufacturing, and it produces less waste than other techniques, such as starting with a base material that is cut away to make the thing.

3D printers also benefit from being computer-controlled machines, also known as computerized numerical control (CNC) machines, meaning they do what they do with minimal human interaction after the design work is done. They can make many identical copies of a thing one right after the other, and the design can be shared online so that others can make their own copies.

While all 3D printing shares come common features, there are several distinct types of 3D printing that vary in how they produce the print. Fused filament fabrication (FFF), powder bed, or light polymerization, for example, all accomplish 3D printing in very different ways, and each with their own strengths and weaknesses. What works in powder bed 3D printing might not work with FFF 3D printing, and the part you get from light polymerization might not be suitable for the same usage as those made with the other techniques.