Have you reached the age when you have to write long essays and term papers for school? If you're still in elementary school, then those days are probably still ahead of you. If you're in middle school or high school, though, you already know what we're talking about.

Although writing can be a challenging process, if you consider today's conveniences, you might be glad that you're writing in the 21st century rather than in the pre-computer age or even farther back. Can you imagine writing your essay with a quill and ink? How about using a typewriter that doesn't have spell check? Today, you can use a word processor and simply print out your essay when it's finished.

Printers have become so commonplace that you'll find them in many classrooms and homes. Today's models are relatively inexpensive and can even print photograph-quality pictures in color. For years, they've been limited to two dimensions. All of that changed, though, when 3D printing was invented.

A 3D printer isn't anything like a regular printer, however. Instead of printing a simple text document on a single piece of paper, 3D printers can "print" a real three-dimensional object! Sound like magic? It isn't. It's pure science and technology.

The technology behind 3D printing has actually been around for several years. Back in the mid-1980s, Chuck Hull invented a process known as solid imaging or stereolithography. Hull's work set the stage for the amazing leaps this technology would take in subsequent years.

The process of 3D printing starts with a design created with computer-aided design (CAD) or animation modeling software. The design could be for a scale model of a new engine part, a simple toy action figure, or even a prosthetic limb. Once you have your digital blueprint created, you can send it to a 3D printer.

Unlike an inkjet printer that sprays ink onto a piece of paper, 3D printers use similar mechanical print heads to spray or squeeze raw material, including rubber, plastic, paper, metal, or other composite materials, onto a platform. 3D printing is an additive manufacturing process. That means that it creates a three-dimensional object in layers from the bottom up.

For example, to build a simple plastic toy action figure, a 3D printer would heat thin filaments of plastic and squeeze it onto a platform layer after layer, slowly building the three-dimensional toy from the bottom up. To heat the materials they extrude, 3D printers often use lasers or similar devices. 3D printers can even create metal objects by heating metal dust with lasers.

The amount of time it takes to "print" a three-dimensional object can vary from a few hours to several days, depending upon how complex it is. 3D printing has become extremely popular in manufacturing sectors, where new prototypes can be 3D printed in a fraction of the time — and at a fraction of the cost — of making traditional wood or metal prototypes. 3D printing technology has thus streamlined and economized the manufacturing process in many industries.

The future appears bright for 3D printing technology. There are particularly-exciting possibilities for the medical field, where 3D printing may be used to create everything from hearing aids to prosthetic limbs. NASA has even begun testing 3D printers that could be used on space missions to allow astronauts to print things they need on demand!

Wonder What's Next?

Lather, rinse, repeat! Lather, rinse, repeat! Clean hands are the focus of tomorrow's sparkly, shiny Wonder of the Day!