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)

In 2013, the United Nations General Assembly officially designated November 19 as World Toilet Day, which is coordinated by UN-Water in collaboration with governments and partners. Here: An open-air toilet and a hot spring shower are seen in the middle of nowhere on the road to the Krafla geothermal power station and lava fields, near Reykjahlid and Lake Myvatn in northeastern Iceland, on August 19, 2012. (Photo by Mariana Suarez/AFP Photo)

Actress Sophia Loren teases the hair of critic Gene Shalit in New York, Tuesday, February 20, 1979. During the filming of a segment for the NBC television “Today” show. In the background is a large photograph of Miss Loren. The segment is scheduled for airing later this week. (Photo by Dave Pickoff/AP Photo)

Overlooking qingshuitan Wetland Park in the air, thousands of Chinese fir trees turn green. Gaoyou City, Jiangsu Province, China, April 20, 2020. April 22 is world earth day. (Photo credit should read Costfoto/Barcroft Media via Getty Images)

The aerobatic demonstration team of the Italian Air Force, the Frecce Tricolori (“Tricolor Arrows”), fly over the Basilica of Saint Mary of Health as they perform as part of a nationwide tour to show unity and solidarity following the outbreak of the coronavirus disease (COVID-19), in Venice, Italy, May 29, 2020. (Photo by Manuel Silvestri/Reuters)

Canadian fashion model Winnie Harlow and American rapper Doja Cat attend Darren Dzienciol & Richie Akiva's Oscar Party 2021 on April 25, 2021 in Bel Air, California. (Photo by Rochelle Brodin/Getty Images for Darren Dzienciol)

A British RAF Typhoon aircraft escorts a C130 transport plane on its way to Jordan for an airdrop of paratroopers from the U.K.'s 16th Air Assault Brigade as part of an exercise conducted jointly with Jordanian soldiers on Wednesday, June 23, 2021. (Photo by Petros Karadjias/AP Photo)

A man stands on a jetty on the fog-shrouded Victoria Harbour Wanchai in Hong Kong, China, 22 March 2022. Fog is common in Hong Kong in spr​ingtime when the territory is affected by alternate cold and warm air. (Photo by Jerome Favre/EPA/EFE)