Three secondary schoolboys smoking an illicit cigarette in Hyde Park, London. (Photo by Evening Standard/Getty Images). May 1972

Models Felicia Verna and Crystal Boyd wearing Stacey Angela during the Fallen Hearts Fashion Experience at Symphony Space on May 31, 2011 in New York City. (Photo by Jemal Countess/Getty Images)

A lesser or red panda stands on its hind legs at Chiba Zoological Park on May 20, 2005 in Chiba, Japan. The panda can maintain the position for over 10-20 seconds at a time. (Photo by Koichi Kamoshida/Getty Images)

Casablanca hosts in May every two years (even years), the largest auto show in Morocco. In 2010, the show had attracted nearly 250,000 visits and helped sell 6,000 vehicles.

Children dressed in festival costume sit on the huge paper doll of historical Japanese figure named Hashi-Benkeii on the carts during the Mikuini annual festival on May 20, 2014 in Sakai, Japan. The annual festival takes place from May 19-21 and is attended by thousands of visitors. During the festival people dressed in traditional Japanese costumes pull carts carrying 6 meter high dolls of Japanese historical figures through the narrow streets. The origins of the festival are unclear but its history can be traced back more than 250 years. (Photo by Buddhika Weerasinghe/Getty Images)

Skateboarding in New York City as pictured by photographer Bill Eppridge in 1965. Pictures originally featured in Life Magazine on May 14, 1965

A villager pours brine into troughs at ancient salt fields on May 5, 2005 in Yantian Village on Hainan Island, China. (Photo by China Photos/Getty Images)

Raising a flag over the Reichstag is a historic World War II photograph taken during the Battle of Berlin on 2 May 1945, by Yevgeny Khaldei.