Resources are broadly classified into natural, human-made and human. Natural resources are those that are taken from nature. They are used without modifying them, i.e. in the same form as they exist in. Rivers, lakes, air, soils, minerals, trees, mountains, etc. are natural resources. Human-made resources have not been provided to us by nature. Human beings have used their intelligence to manufacture them for their own use. Examples include vehicles, buildings, roads, telephone, etc.
Human resources include people who serve us in any way. A teacher, doctor, carpenter, cobbler, etc are human resources.
On the basis of level,of development, a resource can be actual or potential. An actual resource is one which is used currently. We know their quantity. A potential resource is one whose utility is not known at present or is not used despite having utility; instead it may be useful at some time in future. It means that it has the potential to have utility, although it does not have any today.
On the basis of origin, a resource can be abiotic or biotic. A biotic resource is one that has life. An abiotic resource is non-living. Natural resources may also be classified as renewable and non¬renewable. A renewable resource can be used without any risk of its ending up. They exist in unlimited quantity. On the other hand, use of non-renewable resources need to be controlled since once they end up, they cannot be renewed.
On the basis of distribution, a resource can be ubiquitous or localised. A ubiquitous resource is found everywhere. A localised resource is however found in certain parts of the world only.