Bella Hadid arrives at a Dior dinner party during the 72nd annual Cannes Film Festival at on May 15, 2019 in Cannes, France. (Photo by Pierre Suu/GC Images)

Imaan Hammam and Rihanna attend the FENTY x Webster Pop-up Cocktail at The Webster on June 18, 2019 in New York City. (Photo by Dimitrios Kambouris/Getty Images for Fenty)

A woman with an elaborate hat poses during Glastonbury Festival at Worthy farm in Somerset, Britain on June 27, 2019. (Photo by Henry Nicholls/Reuters)

(L-R) Shiri Appleby and Kevin Zegers of “What Just Happened??! with Fred Savage” attend the Pizza Hut Lounge at 2019 Comic-Con International: San Diego on July 19, 2019 in San Diego, California. (Photo by Presley Ann/Getty Images for Pizza Hut)

In this photo released by the Newton Fire department, a juvenile raccoon looks out from a grate after getting stuck in Newton, Massachusetts on August 1, 2019. The fire department was able to rescue the raccoon and free him from the grate. (Photo by HO/Newton Fire Department/AFP Photo)

This image released by Paramount Pictures shows American singer Andra Day in “The United States vs Billie Holiday”. Day accepted the award best actress in a motion picture drama at the Golden Globe Awards on Sunday, February 28, 2021. (Photo by Takashi Seida/Paramount Pictures via AP Photo)

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.