Earth Hour is a global event organized by WWF (World Wide Fund for Nature, also known as World Wildlife Fund) and is held on the last Saturday of March annually, asking households and businesses to turn off their non-essential lights and other electrical appliances for one hour to raise awareness towards the need to take action on climate change. Earth Hour was conceived by WWF and The Sydney Morning Herald in 2007, when 2.2 million residents of Sydney participated by turning off all non-essential lights. Following Sydneys lead, many other cities around the world adopted the event in 2008. Earth Hour 2010 took place on March 27, 2010 from 8:30 p.m. to 9:30 p.m., at the participants respective local time.
Which social networking site is better?