Also known as additive manufacturing, 3D printing fabricates parts by "printing" them whole from digital data, one wafer-thin layer at a time. To date, the technology has mainly been used as a cost-effective way to create models and design prototypes. Increasingly, however, 3D printing is moving onto the factory floor with major manufacturers from auto parts makers to energy companies hoping they will soon be able to create a vast array of parts, equipment and machinery on demand, where and when they need them. 3D Systems says it has seen increased demand for its printers across several industries, as the technology "promises to revolutionize manufacturing." Last year the company recorded a 242% increase in the number of units sold. Revenue -- generated by the sale of printers and related print materials and services -- increased 44%. -- N.S.