A truck driver, butcher and firefighter are some of the subjects in the latest project by the photographer Chris Crisman. This series portrays women at work and focuses on occupations traditionally seen as male dominated. Here: Firefighter Mindy Gabriel, from Upper Arlington, Ohio. (Photo by Chris Crisman/The Guardian)

“Liu Bolin is an artist born in China’s Shandong province in 1973, and he earned his Bachelor of Fine Arts from the Shandong College of Arts in 1995 and his Master of Fine Arts from the Central Academy of Fine Arts in Beijing in 2001. His work has been exhibited in museums around the world. Also known as “The Invisible Man”, Liu Bolin's most popular works are from his “Hiding in the City” series; photographic works that began as performance art in 2005”. – Wikipedia. (Photo by Reuters/China Daily)

Retired teacher Geoff Ostling displays his tattooed skin at a portrait session at his home in Petersham on May 11, 2009 in Sydney, Australia. The 62-year old has pledged to donate his skin to the National Gallery in Canberra after his death. Ostling, who did not get his first tattoo until he was in his forties, is now covered in the artwork by artist eX de Merci from neck to ankle with the theme 'all the flowers of a Sydney garden'. (Photo by Lisa Maree Williams/Getty Images)

In this photo taken April 15, 2015, Clay Hielscher of Overbrook, Kan., poses for a photo in his home made Iron Man suit. While he enjoys building the battlesuits of his favorite super hero, Hielscher said the real reason he is so passionate about his pastime is his 11-year-old daughter, Kyrianna. They design and construct the suits together. (Photo by Chris Neal/AP Photo/The Topeka Capital-Journal)

Bibi rides her bike on the Playa during the Burning Man 2015 “Carnival of Mirrors” arts and music festival in the Black Rock Desert of Nevada, August 31, 2015. Approximately 70,000 people from all over the world are gathering at the sold-out festival to spend a week in the remote desert to experience art, music and the unique community that develops. (Photo by Jim Urquhart/Reuters)

Two robotic legged squad support system (LS3) machines by the Defense Advanced Research Project Agency follow a technician during a demonstration at Joint Base Myer-Henderson Hall, Virginia, on September 10, 2012. (U.S. Marine Corps photo by Sgt. Mallory S. VanderSchans via The Atlantic)