3D printing or additive manufacturing is a process of making three dimensional solid objects from a digital file. The creation of a 3D printed object is achieved using additive processes. In an additive process an object is created by laying down successive layers of material until the entire object is created. Each of these layers can be seen as a thinly sliced horizontal cross-section of the eventual object.How does 3D printing work? It all starts with making a virtual design of the object you want to create. This virtual design is made in a CAD (Computer Aided Design) file using a 3D modeling program (for the creation of a totally new object) or with the use of a 3D scanner (to copy an existing object). A 3D scanner makes a 3D digital copy of an object. 3d scanners use different technologies to generate a 3d model such as time-of-flight, structured / modulated light, volumetric scanning and many more. Recently, many IT companies like Microsoft and Google enabled their hardware to perform 3d scanning, a great example is Microsoft’s Kinect. This is a clear sign that future hand-held devices like smartphones will have integrated 3d scanners. Digitizing real objects into 3d models will become as easy as taking a picture. Prices of 3d scanners range from very expensive professional industrial devices to 30 USD DIY devices anyone can make at home. To prepare a digital file for printing, the 3D modeling software “slices” the final model into hundreds or thousands of horizontal layers. When the sliced file is uploaded in a 3D printer, the object can be created layer by layer. The 3D printer reads every slice (or 2D image) and creates the object, blending each layer with hardly any visible sign of the layers, with as a result the three dimensional object. Examples & applications of 3D printing Applications include rapid prototyping, architectural scale models & maquettes, healthcare (3d printed prosthetics and printing with human tissue) and entertainment (e.g. film props). Other examples of 3D printing would include reconstructing fossils in paleontology, replicating ancient artifacts in archaeology, reconstructing bones and body parts in forensic pathology and reconstructing heavily damaged evidence acquired from crime scene investigations. 3D printing industry The worldwide 3D printing industry is expected to grow from $3.07B in revenue in 2013 to $12.8B by 2018, and exceed $21B in worldwide revenue by 2020. As it evolves, 3D printing technology is destined to transform almost every major industry and change the way we live, work, and play in the future. Medical industry The outlook for medical use of 3D printing is evolving at an extremely rapid pace as specialists are beginning to utilize 3D printing in more advanced ways. Patients around the world are experiencing improved quality of care through 3D printed implants and prosthetics never before seen. Bio-printing As of the early two-thousands 3D printing technology has been studied by biotech firms and academia for possible use in tissue engineering applications where organs and body parts are built using inkjet techniques. Layers of living cells are deposited onto a gel medium and slowly built up to form three dimensional structures. Aerospace & aviation industries The growth in utilisation of 3D printing in the aerospace and aviation industries can, for a large part, be derived from the developments in the metal additive manufacturing sector. NASA for instance prints combustion chamber liners using selective laser melting and as of march 2015 the FAA cleared GE Aviation’s first 3D printed jet engine part to fly: a laser sintered housing for a compressor inlet temperature sensor. Automotive industry Although the automotive industry was among the earliest adopters of 3D printing it has for decades relegated 3d printing technology to low volume prototyping applications. Nowadays the use of 3D printing in automotive is evolving from relatively simple concept models for fit and finish checks and design verification, to functional parts that are used in test vehicles, engines, and platforms. The expectations are that 3D printing in the automotive industry will generate a combined $1.1 billion dollars by 2019. Industrial printing In the last couple of years the term 3D printing has become more known and the technology has reached a broader public. Still, most people haven’t even heard of the term while the technology has been in use for decades. Especially manufacturers have long used these printers in their design process to create prototypes for traditional manufacturing and research purposes. Using 3D printers for these purposes is called rapid prototyping. Why use 3D printers in this process you might ask yourself. Now, fast 3D printers can be bought for tens of thousands of dollars and end up saving the companies many times that amount of money in the prototyping process. For example, Nike uses 3D printers to create multi-colored prototypes of shoes. They used to spend thousands of dollars on a prototype and wait weeks for it. Now, the cost is only in the hundreds of dollars, and changes can be made instantly on the computer and the prototype reprinted on the same day. Besides rapid prototyping, 3D printing is also used for rapid manufacturing. Rapid manufacturing is a new method of manufacturing where companies are using 3D printers for short run custom manufacturing. In this way of manufacturing the printed objects are not prototypes but the actual end user product. Here you can expect more availability of personally customized products. Personal printing Personal 3D printing or domestic 3D printing is mainly for hobbyists and enthusiasts and really started growing in 2011. Because of rapid development within this new market printers are getting cheaper and cheaper, with prices typically in the range of $250 – $2,500. This puts 3D printers into more and more hands. The RepRap open source project really ignited this hobbyist market. For about a thousand dollars people could buy the RepRap kit and assemble their own desktop 3D printer. Everybody working on the RepRap shares their knowledge so other people can use it and improve it again. Future It is predicted by some additive manufacturing advocates that this technological development will change the nature of commerce, because end users will be able to do much of their own manufacturing rather than engaging in trade to buy products from other people and corporations. 3D printers capable of outputting in colour and multiple materials already exist and will continue to improve to a point where functional products will be able to be output. With effects on energy use, waste reduction, customization, product availability, medicine, art, construction and sciences, 3D printing will change the manufacturing world as we know it.