A boy stands at the door of a 60-year-old cable car in the town of Chiatura, some 220 km (136 miles) northwest of Tbilisi, September 12, 2013. (Photo by David Mdzinarishvili/Reuters)
Model Heidi Klum attends her 8th Annual Halloween Party at The Green Door on October 31, 2007 in Los Angeles, California. (Photo by Charley Gallay/Getty Images)
U.S. Marines kick in a door while securing a building next to the main hospital in central Baghdad April 15, 2003, which will be used as a temporary Iraqi police headquarters. (Photo by Jerry Lampen/Reuters)
U.S. Capitol Police with guns drawn stand near a barricaded door as protesters try to break into the House Chamber at the U.S. Capitol on Wednesday, January 6, 2021, in Washington. (Photo by Andrew Harnik/AP Photo)
The lava of the Cumbre Vieja volcano reaches the door of a tattoo shop in La Laguna neighborhood, on the Canary Island of La Palma, Spain, December 14, 2021. (Photo by Borja Suarez/Reuters)
Animals destined for the stage of Radio City Music Hall in New York on November 13, 1986 are led to the stage door by their co-stars, the Rockettes dancers. A variety of animals, including camels, sheep and donkeys, will star in an annual Christmas production. (Photo by G. Paul Burnett/AP Photo)
Greyhounds resume racing behind closed doors on June 01, 2020 in Perry Barr, England. Greyhound racing across England is returning as restrictions on sporting events are relaxed during the coronavirus pandemic. (Photo by Clive Mason/Getty Images)
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.