system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5. what is negative voltage?

I like watching science videos on YouTube and I have a very basic understanding of electronics. But I never seem to get the "negative voltage" thing. 

Why is it used and how does it differ from normal voltage.
gpt
Did Obi-wan have the high ground?  Or did Anakin have the low ground?  

Both are correct since its all relative.  Obi-wan was either on a hill (+V) or Anakin was in a ditch (-V), depending on your perspective.