A student attending a winter military camp reacts during a training session in Ansan, south of Seoul January 3, 2013. Hundreds of students between 11 and 17 years old attend winter boot camp training courses every year. The winter courses range from 4 to 14 days at the Blue Dragon Camp run by retired marines, which also offers summer boot camp for students. (Photo by Kim Hong-Ji/Reuters)

Russian soldiers write home while serving on the Eastern Front during World War I, circa 1915. (Photo by Hulton Archive/Getty Images)

A protestor gestures during clashes with police during protests against planned fuel price hikes on March 27, 2012 in Jakarta, Indonesia. Thousands of Indonesians students in big cities all over the county gathered to protest the governments plans to increase the price of subsidized fuel by 30 percent. The Indonesian parliament is currently debating the fuel hikes which would go into effect March 25, 2012 if approved. (Photo by Ulet Ifansasti/Getty Images)

Students take part in a fashion and design entrance examination at Hubei Institute of fine Arts on February 28, 2011 in Wuhan, Hubei Province of China. 202 students took part in the exam and only 24, (10 percent) of them will be enrolled in Hubei Institute of fine Arts. (Photo by ChinaFotoPress/Getty Images). WUHAN, CHINA – FEBRUARY 28

Students from St Andrew's University indulge in a tradition of covering themselves with foam to honour the “academic family” on October 20, 2014, in St Andrews, Scotland. Every November the “raisin weekend” which is held in the university's Lower College Lawn, is celebrated and a gift of raisins (now foam) is traditionally given by first year students to their elders as a thank you for their guidance and in exchange they receive a receipt in Latin. (Photo by Jeff J. Mitchell/Getty Images)

Residents of the Korean port of Inchon surrender to American troops. (Photo by Bert Hardy/Getty Images). 1950

A giant new exhibition space created by famed graffiti artist Banksy opens to the public on May 3, 2008 in London, England. The disused tunnel beneath Waterloo station has been transformed by 30 artists from around the world. The three day event, tagged as the “Cans festival”, also invites the public to add their own stencil art. (Photo by Jim Dyson/Getty Images)

Esau the ape at the piano. (Photo by Reinhold Thiele/Topical Press Agency/Getty Images). Circa 1900