This document defines public policy and discusses its key subfields. Public policy is defined as a government's actions or inactions in response to public problems. There is no single agreed-upon definition, but generally it refers to the choices governments make and the outcomes of those decisions, backed by state authority. The main subfields of public policy are policy analysis, policy evaluation, and policy process. Policy analysis focuses on determining the best policy options, policy evaluation examines the consequences of policies, and policy process studies how and why policies are made.