A client reacts as she is tattooed during the Tattoo Week SP 2016 in Sao Paulo, Brazil, July 23, 2016. (Photo by Paulo Whitaker/Reuters)

For more than 2,000 years, women from the Baiga tribe in the highland district of Dindori, in central India’s Madhya Pradesh state, have been tattooed. Sumintra, 25, from Bona village, has the markings across her forehead, legs and arms. The women who work as tattoo artists are knowledgable about the different types of designs and pigments preferred by various tribes, and their meanings are passed to them by their mothers. The tattooing ‘season’ begins with the approach of winter. (Photo by Ronny Sen/WaterAid/The Guardian)

Street artist Juandres Vera puts the finishing touches to a giant 3d pavement mural of The Beatles on September 23, 2011 in Liverpool, England. The giant 24m long by 6m wide work, entitled “XXL Liverpool” has been commissioned to celebrate the dual 50th anniversary of The Beatles first gig at The Cavern Club and meeting their manager Brian Epstein. The Beatles drawing kicks off The James Carling International Pavement Art Competition which starts on Sunday and will feature more than 50 of the world's best pavement artists (Photo by Christopher Furlong/Getty Images)

Katy Perry attends the European premiere of Katy Perry: «Part Of Me 3D» at Empire Leicester Square on July 3, 2012 in London, England. (Photo by Mike Marsland)

The Royal Air Force aerobatic team, the Red Arrows, perform during The Royal International Air Tattoo at the RAF in Fairford July 11, 2014. (Photo by Stefan Wermuth/Reuters)

A woman is tattooed during the Great British Tattoo Show in Alexandra Palace in north London, Britain May 23, 2015. (Photo by Neil Hall/Reuters)

Mary Jose Cristerna, a Mexican known as The Vampire Woman, poses for the public to take portraits of her during the annual Venezuela Tattoo International Expo in Caracas, Venezuela, Thursday, January 29, 2015. Tattoo artists from around the world are gathering for the four-day event that also includes under the skin implants and body piercing. (Photo by Ariana Cubillos/AP Photo)