Indians will join millions across the globe today to switch off lights for an hour at 8.30 pm to observe Earth hour. Earth Hour is an annual international event organised by the World Wide Fund that urges households and businesses across the world to turn off their non-essential lights and electrical appliances for one hour at the appointed time to raise awareness towards the need to take action on climate change. It was launched in Australia in 2007 when 2.2 million individuals and more than 2000 businesses turned off electrical equipments for an hour to take a stand against climate change. In a short span of four years, it has become the largest environmental campaign. This year the message is to go beyond the hour and commit oneself to a more sustainable way of living in everyday life.