A machine can make new things. 
A computer tells a machine how to build things. 

3D printing is a way to build objects. 
One common way is fused deposition modeling, or FDM. FDM uses a thin string of plastic called a filament. The machine melts the plastic and pushes it out. This method is popular for hobbyists. 3D printing can make very complex shapes. It can make parts that are hollow inside. It can also make parts with internal truss structures. These are patterns that make parts strong but light. This helps to use less material and reduce waste. 
In the past, people used these machines to make prototypes. A prototype is a first model of a design. Now, industry uses them to make real parts. Some machines even help build metal bridges.
3D printing is a way to build real objects from digital ideas. 
One common way it works is called fused deposition modeling, or FDM. 
People have been thinking about this idea for a long time. In 1945, a writer named Murray Leinster wrote about a machine that could build things. He imagined an arm that followed drawings to make plastic objects. Later, in 1971, Johannes F. Gottwald patented a device for metal fabrication. In the 1980s, many inventors began working on real machines. Hideo Kodama invented a way to make plastic models in 1980. He used a special light to harden plastic in specific patterns. 
Many important patents helped create the printers we use today. In 1984, Bill Masters filed a patent for an automated manufacturing system. That same year, other inventors filed for a process called stereolithography. Chuck Hull later formed 3D Systems Corporation to release the first commercial printer. His machine was called the SLA-1 and came out around 1987. 
3D printing connects digital worlds to our physical world. 

3D printing, also known as additive manufacturing, is the process of creating three-dimensional objects from digital files. These files are often created using computer-aided design (CAD) software. Unlike traditional manufacturing, which often removes material to create a shape, additive manufacturing builds objects by adding material together. This is done under computer control, typically by depositing material layer by layer. 
The mechanism of 3D printing depends on the specific process being used. One of the most common methods is fused deposition modeling (FDM). In FDM, the machine uses a continuous filament of thermoplastic material. The printer melts this plastic and extrudes it through a nozzle to trace a path. 
There are several distinct types of additive manufacturing technologies. FDM is widely used for hobbyist and consumer-oriented models because it is accessible. Stereolithography (SLA) is another major process. It uses a light source, such as a laser, to harden liquid resin into specific layers. 
The history of this technology began with science fiction and moved into real-world patents. In 1945, writer Murray Leinster described a "constructor" in a short story. He imagined an arm that followed drawings to harden plastic in the air. In 1971, Johannes F. Gottwald patented a Liquid Metal Recorder for metal fabrication. In the 1980s, real development accelerated. Hideo Kodama invented two additive methods for plastic models in 1980. He used UV exposure to control the hardening of polymers. Although he filed a patent in 1981, his project was eventually terminated due to a lack of interest and a very small research budget of only 60,000 yen.
Several key figures laid the foundation for modern systems in the 1980s. In 1984, Bill Masters filed a patent for a computer-automated manufacturing system. This is recorded as the first 3D printing patent in history. That same year, Alain Le Méhauté and his team filed for stereolithography, though their application was abandoned. Chuck Hull later became a central figure in the industry. He filed a patent for a stereolithography system and created the STL file format. The STL format is still used for digital slicing and infill strategies today. Hull's company, 3D Systems Corporation, released the SLA-1, the first commercial 3D printer, around 1987. 
Another major breakthrough came in 1988 from S. Scott Crump. He developed fused deposition modeling (FDM), which is the technology most people recognize today. His company, Stratasys, marketed the first FDM machine in 1992. This technology is highly valued in industries like jewelry making, where hot-melt thermoplastics are used for metal investment casting. In the early days, owning such a machine was very expensive, costing upwards of $30,000. Today, the technology has moved from expensive industrial tools to common consumer devices. This evolution has enabled "on-demand manufacturing," where parts are made exactly when they are needed.
Today, additive manufacturing connects digital mathematics to physical reality. It is used in diverse fields, from fashion to heavy engineering. Designers can create 3D-printed necklaces or even complex jet engine models. 

🖼️ Images & Media (14)
+ 2 more
More to explore
✨ What else?
Related topics you might enjoy
🔬 Go deeper
More advanced topics to explore
🪜 Step back
Simpler topics to build understanding
What is Nepedia?
A free, ad-free encyclopedia for children. Every article is written at five reading levels, so the same page works for a five-year-old and a fifteen-year-old — use the level switcher above to see this one change. No account needed to read.