Soviet Army soldiers sit on their tanks in front of the Czechoslovak Radio station building in central Prague during the first day of Soviet-led invasion to then Czechoslovakia on August 21, 1968. (Photo by Libor Hajsky/Reuters)

Tourists take a “selfie” as demonstrators burn a trash container during a May Day rally in Barcelona, Spain, on May 1, 2014. Tens of thousands of workers marked May Day in European cities with a mix of anger and gloom over austerity measures imposed by leaders trying to contain the eurozone's intractable debt crisis. (Photo by Manu Fernandez/Associated Press)

Some 300 girls and women in India still practise open defecation. Over half the country’s population, 800 million people, do not have access to a toilet that meets basic standards. (Photo by Poulomi Basu/WaterAid)

Popular Mobilization Forces (PMF) fires towards Islamic State militants during a battle with Islamic State militants, west of Mosul, Iraq February 22, 2017. (Photo by Reuters/Stringer)

A selection of winning images from the Life in Another Light photo contest 2020, from Kolari Vision. Here: Lights and Shadows in the Dolomites, in the landscape infrared category. (Photo by Tomasz Grzyb/Kolari Vision)

A model is seen backstage before the Manish Arora Spring/Summer 2019 women's ready-to-wear collection show during Paris Fashion Week in Paris, France, September 27, 2018. (Photo by Stephane Mahe/Reuters)

A woman gets a pedicure in Port-au-Prince, Haiti, on October 13, 2017. (Photo by Andres Martinez Casares/AP Photo)

For the Torajan people of Indonesia, death is part of a spiritual journey: families keep the mummified remains of their deceased relatives in their homes for years – and traditionally invite them to join for lunch on a daily basis – before they are eventually buried. Here: Todeng died in 2009. A young relative of his, Sam, lights him a cigarette and changes his glasses. (Photo by Claudio Sieber Photography/The Guardian)