Resources are classified on the basis of status of development in the following categories:---- â—(i) Potential Resources - These are resources that have been found in a region but not yet been fully utilised. â—(ii) Developed Resources - These are resources which have been surveyed and their quality and quantity have been determined for utilisation. The development of these resources depends upon technology and feasibility. â—(iii) Stock - Stock are the materials in the environment which have the potential to satisfy human needs. However, human beings do not have the appropriate technology to access these resources. â—(iv) Reserves - These are stocks of resources that can be put to use with existing technology. However, their use has not yet been started. They can be used to meet future requirements