A developed country, or advanced country, is a sovereign state that has a high quality of life, developed economy, and advanced technological infrastructure relative to other less industrialized nations. Most commonly, the criteria for evaluating the degree of economic development are the gross domestic product (GDP), gross national product (GNP), the per capita income, level of industrialization, amount of widespread infrastructure and general standard of living. Which criteria are to be used and which countries can be classified as being developed are subjects of debate. Different definitions of developed countries are provided by the International Monetary Fund and the World Bank; moreover, HDI ranking is used to reflect the composite index of life expectancy, education, and income per capita. In 2023, 40 countries fit all four criteria, while an additional 19 countries fit three out of four.
The Human Development Index (HDI) is a statistical composite index of life expectancy, education, and per capita income indicators, which is used to rank countries into four tiers of human development. A country scores a higher level of HDI when the lifespan is higher, the education level is higher, and the gross national income GNI (PPP) per capita is higher. It was developed by Pakistani economist Mahbub ul-Haq and was further used to measure a country's development by the United Nations Development Programme (UNDP)'s Human Development Report Office.
Thailand is variably divided into different sets of regions, the most notable of which are the six-region grouping used in geographic studies, and the four-region grouping consistent with the Monthon administrative regional grouping system formerly used by the Ministry of Interior. These regions are the largest subdivisions of the country.
Capital Region of Denmark 
Denmark 
Central Denmark Region 
Region of Southern Denmark 
North Jutland Region 
Region Zealand