Ergo as a currency

The ”The Ecology of Money“ book by Richard Douthwaite states the following
questions about a currency:

  1. Who creates the money?
  2. Why do they create money?
  3. How do they create money?
  4. When do they create money?
  5. What gives money its value?
  6. Where is the money created?
  7. How well does the money work?
  8. Is the money compatible with sustainability?

So I start this topic to gradually collect all possible answers on all the questions.