This document defines key terms related to natural resource economics and explains why studying it is important. Natural resources are aspects of nature that are useful to humans, and natural resource economics applies economic principles to manage resources efficiently for both current and future human needs. It involves evaluating the costs and benefits of decisions regarding resources. The document also classifies natural resources into different categories such as flow versus fund resources, and renewable versus nonrenewable. Overall, natural resource economics improves resource management and decision-making by incorporating economic considerations into how we understand and utilize the natural world.