There is no multi-national or other organizations that uses the name “Global South” and thus no clear cut definition of which countries are included when you use that term. In general, this is the most recent way to talk about the poorer countries with “emerging markets”, formerly known as “developing” economies, and before that the “3rd World”.
The video below from TLDR does a good job explaining not just what is the Global South, but also how it aligns with the Nonaligned Movement from the Cold War, and how this all gets tricky as some of the countries in the “South” are in recent years richer than some of the countries in the Global North.
