A developing country is a country with a less developed industrial base and a low Human Development Index (HDI) relative to other countries. However, this definition is not universally agreed upon. There is also no clear agreement on which countries fit this category. The term low and middle-income country (LMIC) is often used interchangeably but refers only to the economy of the countries. The World Bank classifies the world's economies into four groups, based on Gross National Income per capita: high, upper-middle, lower-middle, and low income countries. Least developed countries, landlocked developing countries and small island developing states are all sub-groupings of developing countries. Countries on the other end of the spectrum are usually referred to as high-income countries or developed countries.