Earth Hour is a worldwide movement organised by the World Wildlife Fund (WWF).
Earth Hour is an annual event that takes place on the last Saturday of March.
It encourages individuals, communities and businesses to turn off non-essential electric lights for one hour, from 8:30 pm to 9:30 pm as a symbol of commitment to the planet
More than 100 countries across the world participated in Earth Hour.
It was first started in Sydney, Australia in 2007.