Money. Sadly, it does make the world go around. There are around 180 different types of currency in the world, including the Albanian lek, the Haitian gourde, the Moroccan dirham, and the Zambian kwacha.

But you are more likely to know the slang terms for the US dollar and the British pound than any of those. Do you know where those terms actually came from? Let's take a look.
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WHAT IS DIFFICULTY?  Only a word indicating the degree of strength requisite for accomplishing particular objects; a mere notice of the necessity for exertion; a bugbear to children and fools; only a stimulus to men -- Samuel Warren

The  greatest difficulties lie where we are not looking for them -- Goethe

It has been the glory of the great masters in all arts to confront and to overcome; and when they had overcome the first difficulty, to turn it into an instrument for new conquests over new difficulties; thus to enable then to  extend the empire of science  - Burke

​It cannot be too often repeated that it is not helps, but obstacles, not facilities, but difficulties that make men -- W Matthews
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