A 3-D printer, which has nothing to do with paper printers, creates an object by stacking one layer of material — typically plastic or metal — on top of another, much the same way a pastry chef makes baklava with sheets of phyllo dough.
A California start-up is even working on building houses. Its printer, which would fit on a tractor-trailer, would use patterns delivered by computer, squirt out layers of special concrete and build entire walls that could be connected to form the basis of a house.
It is manufacturing with a mouse click instead of hammers, nails and, well, workers. Advocates of the technology say that by doing away with manual labor, 3-D printing could revamp the economics of manufacturing and revive American industry as creativity and ingenuity replace labor costs as the main concern around a variety of goods.
3-D Printing Is Spurring a Manufacturing Revolution – NYTimes.com.