An iCub robot built by the Italian Institute of Technology tracks a ball in the Robotville exhibition at the Science Museum on November 29, 2011 in London, England. The Science Museum's Robotville exhibition showcases 20 unique and cutting-edge robots from European research laboratories, it is free to enter and runs from December 1–4, 2011. (Photo by Oli Scarff/Getty Images)

Over 1000 New Year revellers, many in fancy dress, braved freezing conditions in the River Forth in front of the Forth Rail Bridge during the annual Loony Dook Swim on January 1, 2012 in South Queensferry, Scotland. Thousands of people gathered last night to see in the New Year at Hogmanay celebrations in towns and cities across Scotland. (Photo by Jeff J. Mitchell/Getty Images)

International artist Yvette Mattern shows her stunning laser rainbow projection, Global Rainbow, on March 1, 2012 in Whitley Bay, England. The light installation celebrates the London 2012 Cultural Olympiad in the north-east of England. The Global Rainbow has previously lit up the skies of Germany, France and the United States. The projection will shine along the North Tyneside coastline for 4 days, before moving to other locations in the UK. (Photo by Bethany Clarke/Getty Images)

“A ball girl is an individual who retrieves balls for players or officials in a variety of sports including association football, American football, tennis, baseball and basketball”. – Wikipedia

Photo: A ball girl runs with 2 balls for Ivo Karlovic of Croatia against Fernando Verdasco of Spain in their second round match during the Mutua Madrilena Madrid Open tennis tournament at the Caja Magica on on May 11, 2010 in Madrid, Spain. (Photo by Clive Brunskill/Getty Images)

James Castrission, “Cas” and Justin Jones “Jonesy” ski across an ice staking rink with two “You Can” patients on August 2, 2011 in Sydney, Australia. In 75 days, the Aussie adventure pair will attempt to cross 2,200 kilometres of Antarctic ice to the South Pole and back on foot to raise money for youth with cancer. The journey will require the two to trek with all the supplies for approximately three months of walking. Cas and Jonesy became the first to kayak unassisted over 3,300 kilometres from New Zealand to Australia in 2008. (Photo by Ryan Pierse/Getty Images)

A feeder trains a Siberian tiger cub at Erdaohe Tiger Park July 2, 2006 in Antu County of Yanbian Chaoxian Autonomous Prefecture, Jilin Province, China. About 15 artificially-fed Siberian tigers from Harbin Siberian Tiger Park are being trained to develop their ability to live in the wild. The wild Siberian tiger is listed as one of the most endangered species in the world, with its existing number estimated at around 400 worldwide, mainly in the northeastern part of China and the Far East of Russia. Reportedly there are more than 1,300 Siberian tigers which have been raised in China. (Photo by China Photos/Getty Images)

A worker puts the final touch to a replica of a giant eagle and pharaons made with lemons and oranges which shows a scene of the movie “Cleopatra” during the Lemon festival in Menton, southern France, February 10, 2016. Some 140 metric tons of lemons and oranges are used to make displays during the 83rd festival, which is themed “Cinecitta”, and runs from February 13 through March 2. (Photo by Eric Gaillard/Reuters)

A visitor poses inside a three story upside-down family sized house at the Huashan Creative Park in Taipei, Taiwan April 7, 2016. Over 300 square meters of floor space of the upside-down house, filled with home furnishings, was created by a group of Taiwanese architects at a total cost of around US$600,000 and took 2 months to complete, according to the organisers. (Photo by Tyrone Siu/Reuters)