What the heck is a "greenhorn"?
It is an English word used to describe that someone is new. In short, someone who is a beginner and someone who still doesn't know the basics.
Yikes. Thought it was a word that only people from a certain country could understand. I expect people to use "beginner", "noob/noobie", or "neophyte". So.. yea.
Welcome, I guess?