Hanoi's separate vocabulary

I returned to Saigon from Hanoi on June 1st. The few weeks I spent up North was filled with interesting stories populated by peculiar characters--some nice, some not so nice, but all with very elaborate vocabularies. I learned a few new words that I never paid attention to before. "Ngo" is corn up north, "lac" is peanuts, and "ling" is zero. Not only did I have to learn a new vocabulary, I also had to learn different rules about how to function in northern society.