Compared with developed countries, developing countries are economically backward countries. Also known as underdeveloped countries. It usually refers to the third world countries, including more than 130 countries in Asia, Africa, Latin America and other regions, accounting for more than 70% of the world's land area and total population. Developing countries have a vast territory, a large population, a vast market and abundant natural resources. There are also many strategic places, which occupy a decisive strategic position in economy, trade and military affairs. China is the largest developing country.

Developing countries used to be colonies and semi-colonies of imperialism.

Major developing countries-China, India, Brazil, African countries, Asian countries (except Japan, South Korea and Singapore), Eastern European countries and Latin American countries.

China, India, Brazil and South Africa are called the basic four countries; China, India, Brazil and Russia are called BRIC countries.

Developed countries, also known as developed countries, refer to countries with high level of economic development, advanced technology and high living standards, also known as industrialized countries and countries with highly developed economies (MEDC). The per capita gross national product (GDP per capita) of most developed countries is relatively high, but they can also achieve a higher per capita gross national product by developing natural resources, and such countries do not necessarily have more advanced technology.

Developed countries are mainly measured from four aspects: high per capita GDP, advanced industrial technology, advanced science and technology and high social welfare. You need to meet the above four points at the same time to be a developed country, and the four criteria are indispensable.

At present, there are only 18 truly developed countries in the world: the United States, Japan, Germany, France, Britain, Italy, Canada, Sweden, Denmark, Norway, Finland, Belgium, Luxembourg, Switzerland, Austria, the Netherlands, Australia and New Zealand. (The first seven of them are the most developed countries, so they are called "Seven Western Countries")

The relationship between these two countries is also called "North-South relations". There is a complex relationship between capital and technology, raw materials and market, and there is also a relationship between control and controlled between exploitation and exploitation. Narrow North-South relations only refer to economic relations. The economic gap between them is also called "North-South gap".

South-South cooperation: cooperation among developing countries

North-South Dialogue: Negotiations between Developed and Developing Countries