Not understanding what's happening in while loop due to confusing video preceding.

Hi all, I'm a beginner at Python, and I'm stuck on understanding what the heck's happening in the code:

for (insert whatever word you want here like mtfuji) in hellos:
      print (mtfuji + "World")

I really, really don't get what the heck the value of mtfuji/dog/cactus (whatever word you want) is. How does the array know what to do with whatever value I decide, how does the array know that each part of the array, now (I guess) named mtfuji know to go to each string in the array and increment one from this, and how does the array know when to stop?

The only real world example that I can come up with that might explain what's happening is let's say we have a mancala board with one stone in each slot, and this whole mancala board is an array named: boardofstones. If we pick up each stone in the array for the time we pick it up the array now names that stone the value we assign, like prettystone. Then when we put the stone down, the array "forgets" that stone was called prettystone and then assigns that same value to the next stone that we pick up...and so forth till we reach the end of the array of stones, but again I don't know how the array knows what to do with the stones and when to stop. But I could be completely wrong in this interpretation of what's happening in the array.

Ultimately, I have no idea how the for loop in the challenge comes up with "Hello World" (and all the other Hellos in other languages + World) and knows when to stop.

*Note: I am a beginner, and I love metaphors/real world examples vs. being referred to StackOverflow, which is very tough for a beginner to think through. So please give answers in as simplistic of a fashion as possible. Thanks.