Concept - Money less society - sci-fi media

I like watching sci-fi movies and tv shows. I had watched Moonbase Alpha, Star Trek, War of the Worlds (both the tv shows and the movie), Babylon 5, Andromeda, Star Wars (episodes 1 through 6 including clone wars), Battlestar Galactica (old and new) and many others I can't remember off hand.

Since I was innocent then and had no care in the world, I did not see any monetary transactions in Star Trek. I have seen some in Star Wars and I do not know where I saw it but there is this scene where the medium of economic exchange was a piece of crystal. In another scene, a small card.

Now how could anyone keep track of their expense and income? How can one planet know if the visitor from another planet has enough credits on him or her? Is there a central or intergalactic data bank? We do know how information can be stored on a card by how can information be stored on a crystal?

For Star Trek, Babylon 5, Star Wars, Andromeda, Battlestar Galactica and the others who have some sort of federation put up, they may have a unified currency and centralized data bank for this purpose.

Based on the transaction in those sci-fi films, I believe that a central data bank can help monitor the flow of currency in a cash less society.

ATMs provide for this sort of process and so does the use of credit cards or debit cards. ATMs, however, end with the cash being deposited to or drawn out from the machine and credit and debit cards need to be paid or reloaded for it to have any further use.

In the book Gaijin by James Clavell, foreigners in Japan trade through barter of by writing promissory notes to that can be used by the vendors to draw cash in exchange of goods and services if and when they return to England.

For money-less transaction, we either transact by barter, leave promissory notes, or draw lines of credit.

More to come!