system
Given the following post, respond as if you're commenting on Reddit:
human
[Star Trek] What are Federation Credits? Why do they exist?

I don't know much about this Federation, but for the most part. I like it. However, when I was deciding which incarnation Earth to visit, I always read about how the Federation and Earth as whole had "moved beyond" the need for money. Yet it seems like these credits just act as a place holder for money. Do people earn them, like a wage? Or are people just given them for a certain amount of time? If it's the latter, why have them at all? I'm really quite confused by all this, dimension hopping is quite tiring, though I can tell that this galaxy has some pretty nice things (HERE I COME RISA!)
gpt
Federation credits are the currency of the United Federation of Planets. While the Federation internally has moved beyond most uses of currency, like goods (which are now replicated) or services (most of which is free), credits are necessary for some rare goods and services within the Federation and, more importantly, vital to trade outside of the Federation. 

Credits outside of the Federation can be used in purchasing goods and services from the Federation. Since the Federation is peaceful, large, and powerful, it stands to reason that it is also a major economic power in the quadrant, with a healthy supply of technology, goods, and services that parties outside of the Federation might be interested in purchasing. While direct trade can be a medium, currency is far superior in trade.