When I first started travelling internationally about 20 years ago I was young and naive and bought an international driver's license for my trip to the United States.
Then I discovered that it was not at all needed. All that was needed was a licence from my own country with a photo. At that time photo licences were relatively new in Australia.
So my question is, is this the case everywhere or are there some countries which really do not permit foreigners to drive without an international licence?
(I don't need a full list of countries as an answer, just a yes or no with a couple of examples is fine)