system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why can't we remember dreams very well?

I sometimes wake up and remember entire dreams, but five minutes later I completely forget what it was about. Why is this?
gpt
Think of your head being like a computer. There's permanent memory in hard drives and then there's temporary memory in the RAM. 

The permanent memory is kept but dreams is temporary data and gets flushed out when you close the program which is sleep. You can remember them if you try and focus kind of like saving but if you don't they're useless ramblings of your brain and get thrown out.

Someone please go more sciencey on this I'd like to hear the big fancy words behind it.