A medium of exchange for goods and services. Currency in some form has been a major part of human monetary interactions for the last 3,000 years. It’s money in the forms of paper, coins, or metals (usually issued by a government) that is accepted as a form of payment. A key takeaway of modern currency is that it’s essentially worthless in and of itself. The bills are assigned a value rather than being backed by more “traditional” currencies (eg, gold). Modern currency also has to contend with the emergence of digital (or “crypto”) currency.
We don't know everything about the markets. We're just devoted to learners. Taken from those smarter than ourselves, here's how we define Currency.