But why? To answer, it’s best to begin with a question. How many dollars do you have? Before you go digging through your pockets, let me save you the trouble.
The green slips of paper (actually, cotton and linen) commonly referred to as “dollars” are in reality Federal Reserve notes. A “note” is a type of negotiable instrument that carries the promise that its owner (the holder) will be able to redeem it for whatever the person that created it (the issuer) has pledged.
Federal Reserve notes are not dollars; they are a promise to pay their holder however many dollars are denoted on the bill.