Gayri Safi Yurtiçi Hasıla (GSYİH) is a key economic indicator that measures the total value of all goods and services produced within a country's borders over a specific period, usually a year. It reflects the economic performance and health of a nation, providing insights into its productivity and living standards. GSYİH includes various components such as consumption, investment, government spending, and net exports. It is often used by policymakers and economists to assess economic growth, compare economic performance between countries, and make informed decisions regarding fiscal and monetary policies.