I always refer to money as the stuff in my pocket or on my bank account. Having lived in Geneva for many years, I was, of course, used to a lot of different currencies.
But I learned about the real difference between currencies when I discovered LETS and professional barter companies with as “private” currencies vs the “national” or “public” ones we are used to.
This article goes at length into the difference between money and currency and ends by saying “central banks erode – and in some cases destroy – the value of their currencies.
To me, that is the purchasing power of a currency. The money that I save for my pension while I’m in my twenties is worth much more than what I get when I’m old enough. That is the long term effect of compounding interest on interest via National or Public Debts that must be called a “generational crime”.