It is like a laboratory of the Earth that provides a surrounding to everyone in which every human being, microbe and animal can grow. Oceans, river, air, wind and solar energy are the main sources of nature. Man has cared for and investigated into the secrets of nature and its forces. Man has turned almost every force of nature to his own gain, thus making his life richer and more comfortable. Oceans and rivers of the world are the greatest force of nature.
Man dominates over the ocean by using ships as a means of transport.
Man has made an excellent use of rivers too. Rivers are used for irrigation purposes, to obtain hydroelectric power, river valley projects and also as a means of inland transport. Electricity is a force of nature and it is used in man's daily life, in every field of energy. Man has conquered the air and has also conquered space. Man has also discovered atomic energy, which is used to treat diseases and improve crops.