A young man, who says he is part of a local criminal gang, poses for a picture holding a gun in the neighbourhood of Korogcho in Nairobi, Kenya, March 19, 2015. Around 2 million people live in the shantytowns packed in around Kenya's capital. Crime is high amid chronic unemployment levels, while basic services and sanitation are scarce. Residents try to make the best of things, eking out a living and picking up work where they can. (Photo by Siegfried Modola/Reuters)

David Sharp, an engineer with Lockheed Martin, displays the “Samurai Flyer”, an aviation design inspired by the maple seed, during the Association for Unmanned Vehicle Systems International Conference August 16, 2011 in Washington, DC. Lockheed Martin unveiled the new design and demonstrated vertical takeoff and landing, stable hover, and on-board video streaming of the aircraft during their demonstration. (Photo by Win McNamee/Getty Images)

Google has built its first self-driving car prototypes and hopes to test hundreds more models this summer. If all goes well, the company is planning a pilot program in California over the next few years.

Firefighters extinguish a fire in Kampar, Riau province on Indonesia's Sumatra island on August 13, 2019. Indonesian authorities are deploying thousands of extra personnel to prevent a repeat of the 2015 fires, which were the worst for two decades and choked the region in haze for weeks. (Photo by Wahyudi/AFP Photo)

In this Feb. 17, 2017 photo, surfers walk to La Pampilla beach in Lima, Peru. Night surfing apparently came about in Lima because of a dispute with the capital municipality that in 2015 increased the width of a road that runs along the coast. The surfers protested the construction for months by camping on the asphalted beach area, but in the end the municipality prevailed, with support from the police. At the end of 2016, perhaps to win over the surfers, Lima's mayor set up beach lights that allows for night surfing. (Photo by Rodrigo Abd/AP Photo)

Britain's Emma Raducanu hits a return against Sloane Stephens of the US during their women's singles match on day two of the Australian Open tennis tournament in Melbourne on January 18, 2022. (Photo by James Gourley/Reuters)

Getting her tongue pierced was “exciting and scary” says a teen who succumbed to pressure from her best friend in Austin, Texas, February 22, 2008. This image is featured in National Geographic's exhibition “Women of Vision: National Geographic Photographers on Assignment”, on view at the Palm Beach Photographic Centre, Jan. 22 - Mar. 22, 2015. (Photo by Kitra Cahana/National Geographic)

Wang Jiayun, born June 18 1993. Wang’s height is 164cm, her weight 42kg. Wang Jiayun says she was born in Kowloon of Hong Kong Special Administrative Region, and presently lives in Shenzhen City of Guangdong province in China. Identity: High school student. Wang's large eyes, pale face, perfectly structured nose and extremely slim figure resemble a brand of human-sized blow-up doll popular with Korean men. This cute and s*xy barbie doll look a like is hot property. She recently became the No.1 searched name in the country's top search engine, Naver.com. Photo: Wang Jia Yun (王嘉韻 or 왕지아인). (Photo by Wang Jia Yun)