Street fighting in Berlin between Government troops and Spartacists, during the Spartacist uprising which followed Germany's defeat in World War I. (Photo by Keystone/Getty Images). 1919
Soldiers of the 70th division of the American 7th Army hold up a Nazi flag and a portrait of Adolf Hitler, taken during the World War II capture of Saarbrucken. (Photo by Horace Abrahams/Keystone/Getty Images). 22nd March 1945
A young exhibitor arrives with her kitten on a lead at the National Cat Club show at Crystal Palace, London. (Photo by Fox Photos/Getty Images). 2nd December 1931
The Dynasphere, an electrically-driven wheel, invented by Mr. J. A. Purves of Taunton and his son. It had 2.5 horse power and once attained a speed of 25 mph. (Photo by Fox Photos/Getty Images). 1932
Musicians from the Academy of Contemporary Music play using instruments made of car parts during a photocall on April 16, 2008 in London, England. Ford's unique orchestra made up entirely of Ford Focus car parts. (Photo by Daniel Berehulak/Getty Images)
Cast member Shu Qi poses during a photocall for the film “The Assassin” (Nie yin niang) in competition at the 68th Cannes Film Festival in Cannes, southern France, May 21, 2015. (Photo by Eric Gaillard/Reuters)
Tattoos are commonly used among criminals to show gang membership and record the wearer's personal history—such as his or her skills, specialties, accomplishments and convictions. They are also used as a means of personal expression. Certain designs have developed recognized coded meanings. The code systems can be quite complex and because of the nature of what they encode, the tattoo designs are not widely recognized.