Classify resources on the basis of their status of development.

On the basis of the status of development resources can be classified into four types.

(i) Potential resources: These include resources which are found in a region, but have not been utilised. For example, solar and wind energy in Rajasthan and Gujarat respectively.

(ii) Developed resources: These include resources which are surveyed and their quality and quantity have been determined for utilization. For example coal, iron, manganese, etc.

(iii) Stock: Materials in the environment which have the potential to satisfy human needs but human beings do not have the appropriate technology to access them are called stock. For example, geothermal energy.

(iv) Reserves: Resources which can be put into use with the help of existing technical ‘know-how’ but their use has not been started. These can be used for meeting future requirements. For example, water in dams, forests, etc.