system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: High fantasy/Low fantasy

I never really understood it. I know it has something to do with primary and secondary worlds, but what does that even mean?
gpt
Generally high fantasy involves worlds where magic and fantastical creatures are common.  Example: LOTR

Low fantasy is when there are subtle fantastical elements in a more realistic world.  Example: Game of Thrones (at least so far in the first half of book 1)