The G4 economies refer to the four largest economies in the world, which are the United States, Japan, Germany, and the United Kingdom. These countries are often grouped together because of their significant impact on the global economy and their high levels of economic development. The G4 countries are major players in international trade and investment, and their economic policies and decisions can have significant effects on global markets. The term "G4" is commonly used in discussions of international economic policy and cooperation.