What is meant by rainwater harvesting? Name some of the ancient structures used for rainwater harvesting by the rural people.

Rainwater harvesting is the process of recharging the ground water by making the rain water falling on the ground percolate in the land. The structures of rain water harvesting which were used in the ancient times are: Khadins of Rajasthan, Kulhs of Himachal Pradesh and Eris of Tamil Nadu.