The painted nails of a Kurdish Peshmerga female fighter are seen as she takes up a position during combat skills training before being deployed to fight Islamic State militants, at their military camp in Sulaimaniya, northern Iraq September 18, 2014. (Photo by Ahmed Jadallah/Reuters)

Wedges of an orange generate enough current and electrical juice – 3.5 volts – to power an LED. The fruit’s citric acid helps electrons flow from galvanized nails to copper wire in this 14-hour exposure. This image was published in September’s Visions of Earth, a trio of photos that appear in each issue of National Geographic. (Photo by Caleb Charland/National Geographic)

Belgium. Rosalie, 9, goes to school in Brussels. “At my school we have separate toilets for girls and boys on every floor. My classroom is on the 3rd floor. We have 22 toilets, which are shared between 230 pupils and 20 adults. The teachers at school let us go to the toilet whenever we need to”. (Photo by Tim Dirven/WSUP/Panos)

Bella Hadid attends the “Tre Piani (Three Floors)” screening during the 74th annual Cannes Film Festival on July 11, 2021 in Cannes, France. (Photo by Lionel Hahn/Getty Images)

Dance floor atmosphere at the Daily Front Row's Fashion Media Awards – After Party at The Wooly on September 8, 2017 in New York City. (Photo by Paul Morigi/Getty Images)

A man sits waiting for a train on the London Underground in 1890, when the platform floors were still made from wooden floorboards. (Photo by Hi-Story/Alamy Stock Photo)

A fan watches the group A World Cup match between Mexico and Brazil via a live broadcast at the FIFA Fan Fest in Sao Paulo, Brazil, Tuesday, June 17, 2014. Forget the French manicure. It’s Brazil during World Cup, and women here want to flaunt their love of the national team with wacky nail designs. (Photo by Dario Lopez-Mills/AP Photo)

UK Love Island star Lucie Donlan, 24, goes from appearing on reality TV to treading the boards – as she poses barefoot with a skateboard in California in the first decade of May 2022. (Photo by Instagram)