Human Development Index is a comparative measure of life expectancy, literacy, education, and standards of living for countries worldwide. It is a standard means of measuring well-being, especially child welfare. It is used to distinguish whether the country is a developed, developing, or under-developed country, and also to measure the impact of economic policies on quality of life. The index was developed in 1990 by Pakistani economist Mahbub ul Haq. Countries (almost all UN member states and a couple of special territories) fall into three broad categories based on their HDI: high, medium, and low human development.