What Are The Differences Between Developing, Developed And An Underdeveloped Economy?

Developed countries have infrastructure in place- such as roads, bridges, water pipes, fuel lines, electrical wiring, fiber optic wiring, and septic/sewage and runoff drainage or treatment systems, to name a few- and the technical capacity to take care of all their citizens with such infrastructure services as mechanical repair or maintenance facilities, doctors and medical facilities, etc. In short, a developed country has three things: It has stuff, it has people to take care of that stuff (and of other people), and it has people who make money and give up part of that money to pay for stuff.

a good example is south korea.

a developing country is largely similar, but the existing infrastructure is usually either old or poorly maintained (or both), and the people have less money to spend on stuff and so there are either fewer experts or the quality of the products that they make or the services they provide is lower than in a developed country.

a good example is thailand.

an underdeveloped country has lots of people, but lacks some (or all!) basic infrastructures for some or all of its citizens, and so the people have no stuff and must make money which they are then expected to give to their government, who will then give them stuff. This doesn't often happen, however, because governments in these kinds of countries are invariably so corrupt that calling them 'governments' at all is ridiculous.

a good example is cambodia, burma, or laos.

Developed economies are those economies which have been developed in terms of resources and economic conditions. These include economies from the global north such as Germany, Britain, France, United States of America etc. Developing economies are those economies which are striving to come out of their social, economic and political crisis. They currently lack what developed economies owe such as political stability, strong economic indicators, free market system, democracy etc. The developing economies include economies of global south or rapidly emerging economies such as India, China, Brazil, Turkey etc. These economies have greater chances to become stronger in coming future. However underdeveloped countries are usually referred to third world countries which are in worse conditions as compared to the developing and developed countries. These economies lack political stability, face military intervention, very high poverty line, greater unemployment, greater default risks and greater economic problems.

Differentiate between a developed and developing country

A developed economy is stable and less risky.  A developing country is riskier.  A developed economy abtains stability by a myriad of different industries it has, so that if there is a drop in one, the economy as a whole doesn't suffer (as much), while developing countries are less diverse.

The economy and stability of the currency decides about the status of the country. There are only a few developed countries in the world like America and England but a lot are developing or undeveloped countries where people don't have enough food and clothes to live. UNICEF and other organizations are working in these countries for their health and education.