A resource is a physical material that humans need and value such as land, air, and water. Resources are characterized as renewable or nonrenewable; a renewable resource can replenish itself at the rate it is used, while a nonrenewable resource has a limited supply. Renewable resources include timber, wind, and solar while nonrenewable resources include coal and natural gas. This Audio is based on Geogrpahy NCERT Class 8th (Chapter-1)