Resources are classified on the basis of status of development as given below
(i) Potential resources are resources which-are found in a region, but have not been utilized. The decision to utilize them is based on economic feasibility and its usefulness.
(ii) Developed resources are resources which have been surveyed and their quality and quantity have been determined for utilization. The development of such resources depends on technology and level of their viability.
(iii) Stock resources have the potential to satisfy our needs, but we do not have the appropriate technology to use these economically.
(iv) Reserve resources can be put into use with the help of existing technical ‘know-how’, but their use has not yet been started.