Internally displaced Syrian children play inside a refugee camp in the Hama countryside, Syria January 1, 2016. (Photo by Ammar Abdullah/Reuters)

Gelada baboons (Theropithecus gelada) play in their enclosure at the Zoo in Zurich, Switzerland, Wednesday, May 15, 2013. (Photo by Steffen Schmidt/Keystone/AP Photo)

A British woman plays a piano designed especially for people who are confined to bed. Date: 1935. (Photo by Mary Evans Picture Library/Caters News)

Fashion models Darien Leigh and Valerie Drew play leap-frog on the beach. 2nd July 1956. (Photo by Harry Kerr). P.S. All pictures are presented in high resolution.

A hen, a dog and a rabbit playing cards, circa 1956. (Photo by Evans/Three Lions)

Women playing in the street as the snow falls on Johannesburg for the first time in seventeen years. (Photo by Keystone/Getty Images). 1st September 1962

Children play football in Bujumbura, Burundi on March 19, 2015. (Photo by Carl de Souza/AFP Photo)

A child plays with a soap bubble on the city hall plaza on March 14, 2015 in Paris. (Photo by Dominique Faget/AFP Photo)