Natural resources are assured by nature without any intercession of human beings. They are vital to human survival, since they provide wellness to our future. We can group these resources as perpetually available, renewable over short periods of time, and non-renewable resources.
Perpetually available resources are capable of being renewed and not cause any depletion when used. Sunlight, wind, wave energy are some of the examples of perpetually available resources.
Resources that renewable over short period of time can be destroyed and their excessive usage causes damage on environment, these resources are water, soil, timber, even wildlife.
Non-renewable resources can be depleted due to their formation takes very long time. Oil, coal, minerals, natural gas, copper, aluminum, and other metals, are counted as non-renewable resources.