The history of mediums of exchange goes back centuries, of course. If I have two cows and you have a car and we agree to trade, so be it. Trade is trade, regardless of the medium of exchange.

Federal Reserve Notes
Bitcoin
Gold
Silver
diamonds
rubies
emeralds
cows
pigs
chickens
boats

any items that any two people agree to exchange gets the job done. I was recently told about a local car dealer who has traded cars for cattle.