Natural substances found on the earth that are use without much alteration are called natural resources.

Example- Water, air, soil, minerals and natural vegetation. We can directly consume a tomato from the plant. But we have to separate minerals from there ores from processing. like petroleum, diesel,etc.

So there are criteria in which there natural resources are classified.

If we talk about the classification on the bases of origin. Natural resources are divided in 2 categories. Abiotic and Biotic.

1) Biotic resources- These are derived from all living organism in ecosystem. They include plants such as cereals, crops, fruits, vegetables. Animals, micro-organisms, and human beings also belongs to this category. Most of the biotic component have the capacity to reproduce if the environmental conditions are favorable. Some rare spices of animals are being hunt for there organ or skins, that’s why they are coming under the danger of being extent. Many policies and rules are made to stop this exploitation of life. Example- elephant for teeth, tiger for skin, rhino for there horn, etc

2) Abiotic resources- These are found from physical or non-living environment. They include air, water, land, minerals, etc. Some of these resources can be exhausted by excessive use because they are available in limited quantity in nature. There total reserve cannot be increased by human efforts. These resources are in great demand for the development of industries. Example- coal, petroleum, clean water,etc.