A model backstage during day 1 of Aspen Fashion Week 2011 on March 13, 2011 in Aspen, Colorado.

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.

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)

A masked participant carries a burning matress during the ancient carnival of Zubieta, in the northern Spanish Navarra province on January 30, 2018. The yearly three day festivities, revolving mainly around agriculture and principally sheep hearding, run on the last Sunday, Monday and Tuesday of January where Navarra Valley locals from two villages dress up and participate in a variety of activites as they perform a pilgrimage through each village. (Photo by Ander Gillenea/AFP Photo)

American actress Sarah Hyland at arrivals for 26th Annual Screen Actors Guild Awards – Part 2, Shrine Auditorium, Los Angeles, CA January 19, 2020. (Photo by Monica Almeida/Reuters)

An unidentified man brandishes a gun during a protest against a new citizenship law outside the Jamia Millia Islamia University in New Delhi, India, January 30, 2020. The gunman went live on Facebook to warn he was taking his “final journey” before firing at the protest. (Photo by Danish Siddiqui/Reuters)