A girl attends Friday prayers in front of an army tank in Tahrir Square in Cairo February 18, 2011. Five years ago thousands of protesters took to the streets demanding the end of the 30-year reign of President Mubarak as Egypt became the second country to join the Arab Spring. After weeks of clashes, strikes and protests across Egypt, Mubarak resigned on February 11, 2011. (Photo by Suhaib Salem/Reuters)

“Amy Jade Winehouse (14 September 1983 – 23 July 2011) was a British singer-songwriter known for her powerful contralto vocals and her eclectic mix of musical genres including R&B, soul and jazz. ... Winehouse died at the age of 27 on 23 July 2011 at her home in London; police have said that the cause of her death was «as yet unexplained»”. – Wikipedia

Photo: Amy Winehouse vigil outside Amy Winehouse's North London home on July 23, 2011 in London, England. Singer Winehouse, 27, was found dead today. (Photo by Sylvia Linares/Getty Images)

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)

Imogen Bankier of Scotland (L) and Chris Adcock of England in action during their round one mixed doubles match in the Yonex All England Badminton Open Championship on March 9, 2011 in Birmingham, England.

Zhang Ze of China in action during his Oceania zone group1 match against Bernard Tomic of Australia of the 2011 Davis Cup on July 8, 2011 in Beijing, China. (Photo by Lintao Zhang/Getty Images)

A woman walks in central Rason city, northeast of Pyongyang, August 29, 2011. (Photo by Carlos Barria/Reuters)

Girls sits on a bench during summer at the Central Park in New York, United States, 2011. (Photo by An Rong Xu)