In this October 8, 2017, photo, Emily Lynch reacts to hitting her first clay target during a training session for the Trigger Warning Queer & Trans Gun Club in Victor, N.Y. A gay, lesbian and transgender group concerned that extremists have become more emboldened and dangerous have decided to take up arms. The gun club meets once a month to shoot long guns in a field in upstate New York. (Photo by Adrian Kraus/AP Photo)

Keira Knightley attends the premiere for “A Dangerous Method” at The 55th BFI London Film Festival at The Odeon West End on October 24, 2011 in London, United Kingdom. (Photo by Dave Hogan/Getty Images)

Two Bunny Girls from the Playboy Club and two Penthouse Pets from the Penthouse Club prepare to take part in the annual Good Friday waiters and waitresses race in Battersea Festival Gardens, London, 28th March 1972. (Photo by Ian Showell/Keystone/Hulton Archive/Getty Images)

Balinese girls in traditional costumes gather during a parade for this year's last sundown in Bali island, Indonesia Thursday, December 31, 2015. (Photo by Firdia Lisnawati/AP Photo)

Director Pawel Pawlikowski holds his Oscar for best foreign language film for “Ida”, with presenters Chiwetel Ejiofor (L) and Nicole Kidman during the 87th Academy Awards in Hollywood, California February 22, 2015. (Photo by Lucy Nicholson/Reuters)

The selfie is the most popular photography trend of the internet today. It's gotten so popular, in fact, that even our beloved feline friends have started to catch on. I dare you to keep the smile off your face for this one!

Throughout the course of the long war in Afghanistan, Coalition troops have relied on thousands of military working dogs to help keep them safe, and make their jobs easier. The dogs are trained to detect explosives, to find illegal drugs, to search for missing comrades, or target enemy combatants. Not only are they active on the front lines, but behind the lines they serve as therapy dogs, service dogs, and loyal companions. They also share the same risks as the ground troops, suffering injuries and sometimes death on the battlefields. Gathered here are images of these dogs and their handlers in Afghanistan and back home, from over the past several years, part of the ongoing series here on Afghanistan.