In this photograph taken on February 18, 2016, Pakistani children ride on swings in the predominantly Pashtun Korangi District of Karachi. In a rundown district of Karachi, Rabia balks at a neighbour's proposal to vaccinate her children, demonstrating one of the biggest hurdles to eradicating polio in Pakistan by the end of the year: confused and frightened parents. (Photo by Asif Hassan/AFP Photo)

Women pose for a photograph in traditional Ethiopian dress during the annual Timkat Epiphany celebration on January 19, 2017 in Gondar, Ethiopia. Timkat is the Ethiopian Orthodox Christian festival which celebrates the baptism of Jesus in the Jordan river. During the festival, Tabots, or models of the Ark of the Covenant, are taken from churches around Gondar and paraded through the streets to Fasilides Bath. (Photo by Carl Court/Getty Images)

A tourist take a photograph of a sulphur lake in the Danakil Depression on January 23, 2017 near Dallol, Ethiopia. The depression lies 100 metres below sea level and is one of the hottest and most inhospitable places on Earth. Despite the gruelling conditions, Ethiopians continue a centuries old industry of mining salt from the ground by hand in temperatures that average 34.5 degrees centigrade but have risen to over 50 degrees. (Photo by Carl Court/Getty Images)

A man takes a photograph of his friend as thick smoke rises from a fire, which broke out at oil wells set ablaze by Islamic State militants before they fled the oil-producing region of Qayyara, Iraq, January 28, 2017. (Photo by Muhammad Hamed/Reuters)

This photo series shows curvy canines and flexible felines participating in a spot of yoga. The shots feature the animals in the likes of the lotus position, balancing on two legs, and stretching in ways that would make the greatest of yoga masters proud. Photographer Dan Borris came up with the idea for the series in 2000, when he was asked by a friend to photograph her in a yoga pose while her dog bothered her. Pictured: Wally. (Photo by Dan Borris/Caters News)

“Today, we take photography for granted. Anyone can take a photograph simply by pressing a button. Yet, it was not always so simple. The invention of photography was announced in 1839, but during its first fifty years taking a photograph was a complicated and expensive business. In 1888, all this was to change following the appearance of a camera that was to revolutionize photography. Popular photography can properly be said to have started 120 years ago with the introduction of the Kodak”. – The UK National Media Museum. Photo: Two men on the deck of a ship, about 1890. (Photo by Collection of National Media Museum/Kodak Museum)

A visitor looks at pictures of French photographer Jacques-Henri Lartigue (1894-1986), on July 1, 2013 during the 44thd annual Rencontres d'Arles photography festival in Arles, southern France. The event runs until September 22. (Photo by Boris Horvat/AFP Photo)