What is money?

According to Dr. Steve Sjuggerud, this is the guarantee on a $20 bill from the 1920s:

"This certifies that there have been deposited in the Treasury Twenty Dollars in gold coin payable to the bearer on demand."

Today, our $20 bill says:

"This note is legal tender for all debts public and private."

What exactly does that mean? According to the Treasury Department's explanation:

"Federal Reserve notes are not redeemable in gold, silver or any other commodity, and receive no backing by anything... The notes have no value for themselves, but for what they will buy. In another sense, because they are legal tender, Federal Reserve notes are "backed" by all the goods and services in the economy."

Steve goes on to quote Burt Blumert:

"In plain English, dollar bills have no value," Burt explained. "Yet most Americans hold most of their wealth in them... Think about that."