People inspect hookahs shaped like rifles on display for sale in a souk at the port city of Sidon, southern Lebanon, December 23, 2015. (Photo by Ali Hashisho/Reuters)

People dressed as Father Frost, the equivalent of Santa Claus, and Snow Maiden take part in the contest “Yolka-fest-2014” (Fir-festival-2014) in Minsk December 12, 2014. (Photo by Vasily Fedosenko/Reuters)

Krista Long began snapping pics of people sliding down a water slide after many visits to the local water park with her tween daughters. The result is an action-packed series that show emotions ranging, she says, “from pure joy to fear, in anticipation of the inevitable splash-down!” (Photo by Krista Long)

“Shortly after he arrived, Van Agtmael witnessed the aftermath of this suicide bombing at a cafe that soldiers frequented in Mosul. Nine people died and 23 were wounded”. (Photo and caption by Van Agtmael/Harrison Jacobs/Magnum Photos)

People walk down the street while Hurricane Matthew approaches in Port-au-Prince, Haiti October 3, 2016. (Photo by Carlos Garcia Rawlins/Reuters)

A female soldier from the honour guards prepares for a welcoming ceremony for Uruguay's President Tabare Vazquez at the Great Hall of the People in Beijing, China, October 18, 2016. (Photo by Jason Lee/Reuters)

People watch participants, whose faces are painted as popular Mexican figure “Catrina”, during the annual Catrina Fest, part of Day of the Dead celebrations, in Mexico City, Mexico, November 2, 2016. (Photo by Edgard Garrido/Reuters)

In this photo illustration a package of Nicotine Gum, which is advertised as helping people stop smoking cigarettes, is seen on January 10, 2012 in Miami, Florida. A study published in the journal Tobacco Control on Monday, reported that the nicotine alternatives, like Nicotine Gum, have no lasting effect on people trying to quit their smoking habit. (Photo illustration by Joe Raedle/Getty Images)