"The 3D printer works by building components up in layers of plastic, mainly polylactic acid (PLA), which is a bio-degradable polymer made from lactic acid. The technology already exists, but commercial machines are very expensive. They also can't copy themselves, and they can't be manipulated by users, says Vik Olliver. RepRap has a different idea. The team, which is spread over New Zealand, the UK and the US, develops and gives away the designs for its much cheaper machine, which also has self-copying capabilities. It wants to make the machine available to anybody — including small communities in the developing world, as well as people in the developed world, says Olliver. Accordingly, the RepRap machine is distributed, at no cost, under the GNU (General Public Licence).
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