The original intention of IMF in reality is the World Monetary Fund, which is an economic world organization. In Mission Impossible series, it is a fictional American intelligence agency. Its full English name is Impossible Mission Force, and its full name is Mission Impossible. It means a top secret intelligence organization, specializing in all kinds of seemingly impossible and difficult tasks. The IMF in Mission Impossible is pure fiction and conflicts with the real IMF name. . .

The IMF in the movie is actually equivalent to the CIA in the United States, just a name invented to reduce sensitivity.