Was the whole world really at war during world war ?

Question

Was the whole world really at war during world war ?
Was it or was it just a lot of countries but not all of them? How did all the countries conflicts get tied to one world war and not individual wars?

Answer

No, not every country in the world was involved in combat, but it was a global war in the truest sense. There was fighting on every continent and ocean, and even the countries not involved in actual combat were involved politically, socially, and economically.