barter is when you trade one good or service for another good or service. example: i’ll fix your bike if you mow my law.
money is a physical representation of work, in the form of bills or coins. example: i’ll pay you 20 dollars to mow my lawn.
Credit is a way to purchase goods or services without actually paying now but promising to pay in the future. example: i’ll use my credit card to pay for you mowing the lawn now, but in 1 month i’ll actually pay you the money.