Displaced Sunni people, who fled the violence in the city of Ramadi, arrive at the outskirts of Baghdad, April 17, 2015. Iraqi security forces fought Islamic State militants at the gates of the western city of Ramadi on Friday, and local authorities warned it was in danger of falling unless reinforcements arrived soon. (Photo by Reuters/Stringer)

An Iraqi girl, who fled from Falluja because of Islamic State violence, poses for a photographer at a refugee camp in Ameriyat Falluja, south of Falluja, Iraq, June 16, 2016. (Photo by Ahmed Saad/Reuters)

Nguyen Ngoc Anh, 36, who was an illegal logger turned forest protector poses at Phong Nha National Park, Quang Binh province, Vietnam on April 8, 2022. (Photo by Hoang Trung/Reuters)

Young women wear kimonos to mark “Coming of Age Day” to honour people who turn 20 this year to signify adulthood, in Yokohama, Kanagawa prefecture on January 9, 2023. (Photo by Philip Fong/AFP Photo)

Cybermen patrol the National Museum of Scotland before the opening of the Doctor Who Worlds of Wonder exhibition in Edinburgh, Scotland on Wednesday, December 7, 2022. (Photo by Murdo MacLeod/The Guardian)

Members of the Hitler Youth who are trained to report airstrikes repaining their bicycles. Published by: “Die Sirene”. 1942. (Photo by Herbert Hoffmann/Ullstein Bild via Getty Images)

The Vietnam Slide Project was created by photo editor Kendra Rennick, who began collecting photo slides after a close friend lost her father, a Vietnam veteran. Her friend found a box of slides that her father had taken while in Vietnam and from there Rennick has continued to collect photographs that Vietnam veterans took during their tours of duty. Here: A photo taken from the collection of D.Thornton, who served in the First Air Cavalry division of the United States Army. (Photo by D.Thornton/The Vietnam Slide Project)