Pretty Girls, Ugly Faces is a photo fad in which girls take pictures of themselves while posing in an unflattering manner, making a silly face or performing a physically strenuous activity.

Myouchin Munehisa, 44, as he finishes Hibashi iron bells made of iron on a production line at Myochin Honpo shop on April 25, 2014 in Himeji, Japan. Myochin family's iron business, started in the Heian period (794-1185) of Japan as an armor and helmet maker, shifted as the needs of people changed in the course of history. (Photo by Buddhika Weerasinghe/Getty Images)

Bikers passes along the High Street on March 18, 2012 in Royal Wootton Bassett, England. The ride, in its third and final year and involving thousands of bikers started at Hullavington airfield and aims to honour the people of Royal Wootton Bassett and to raise money for the Afghan Heroes charity. (Photo by Matt Cardy/Getty Images)

The Boeing 747-8 Intercontinental airliner, the company's newest and largest passenger plane, takes off for its first test flight at Paine Field Airport March 20, 2011 in Everett, Washington. The new plane features quieter, more fuel efficient engines, more seating and a redesigned interior.

Three-month old cheetah cubs make their public debut at the Smithsonian National Zoo on July 24, 2012 in Washington, DC. (Photo by T.J. Kirkpatrick)

Pope Francis waves as he arrives at the Kangemi slums on the outskirts of Kenya's capital Nairobi, November 27, 2015. (Photo by Goran Tomasevic/Reuters)

Bao Bao, the Giant Panda cub is seen by the media for the first time January 6, 2014 inside his glass enclosure at the Smithsonian's National Zoo in Washington, DC, a few days before going on display to the general public. Bao Bao was born at the Smithsonian's National Zoo August 2, 2013. (Photo by Paul J. Richards/AFP Photo)

Two Teddy Bears from the 1920's sit on display in the museum section of the Merrythought Teddy Bear shop on April 5, 2011 in Ironbridge, England. Established in 1930, Merrythought has been hand-making Teddy Bears for over 80 years in Shropshire. The family-run company is the last remaining British teddy bear factory and is launching its latest limited edition bear to mark the royal wedding. The Commemorative Royal Wedding bear is limited to 75 and comes after its popular Prince William and Catherine Middleton bears completely sold out. Merrythought has also been selected by the London Olympic Games organisers to produce the official teddy bears of the London 2012 Olympic and Paralympic games. (Photo by Christopher Furlong/Getty Images)