Mario Huettenhofer, chief of the German company 3D Fab, presents his own face as 3d print during the international fairs FabCon 3.D and Rapid.Tech in Erfurt, Germany, Thursday, May 15, 2014. 130 exhibitors from all over the world present the entire world of 3D printing. The trade fairs are accompanied by specialist programs featuring 80 scientists, practitioners and trend analysts from ten countries, who will explain the latest findings, trends and applications for additive processes in industry and for 3D printing in the private sector to newcomers, experts and consumers alike. (Photo by Jens Meyer/AP Photo)

A woman tries a swing in front of a screen featuring New York scenes during the new Air France Exhibition called “Air France, France is in the Air” in New York June 25, 2014. (Photo by Timothy A. Clary/AFP Photo)

This picture was taken in the 1890's and shows a group of loggers hauling a heavy load. It is hard to even picture how they got the logs stacked that high. It is also hard to imagine how they keep it from tipping over.

An Orthodox activist (Right) clashes with a gay rights campaigner during a protest outside of the State Duma, Russian Parliament's lower chamber, in downtown Moscow, January 22, 2013. (Photo by Ilya Pitalev/RIA Novosti)

Egyptian President Hosni Mubarak speaks to the media after talks with German Chancellor Angela Merkel at the Chancellery on April 23, 2008 in Berlin, Germany. (Photo by Sean Gallup/Getty Images)

Doris Pennman adjusts her umbrella as she walks along Mission Beach on January 8, 2005 in San Diego, Califonia. (Photo by Sandy Huffaker/Getty Images)

This handout photo taken on February 12, 2017 and released on February 16 by the International Federation of Red Cross and Red Crescent Societies (IFRC) shows Mongolian herder Munkhbat Bazarragchaa (C) dragging two sheep – which recently died due to the weather - to a pile of dead animals behind his “ger” in Khuvsgul province, northern Mongolia. Thousands of Mongolian herders face disastrous livestock losses from dreaded severe weather known as the “dzud”, the Red Cross said on February 16, 2017 in launching an international emergency aid appeal. (Photo by Mirva Helenius/AFP Photo/IFRC)

A woman promotes a go-go dance bar in Pattaya, Thailand March 25, 2017. With mascots dressed as smiling fish and a police rock band, Thai authorities launched a “Happy Zone” at the weekend to improve the image of a city notorious for sеx tourism. Stung by foreign headlines portraying the seaside resort of Pattaya as “Sin City” and “The World’s Sеx Capital”, Thailand’s junta has begun a new effort to re-brand it. Businesses in the Happy Zone are asked to make the area feel safer, there are increased security patrols, police launched a mobile phone app for visitors to summon them if an emergency occurs. (Photo by Jorge Silva/Reuters)