Have you ever heard about “Coffee Belt”? “Coffee Belt” is referring to the area between Tropic of Cancer and Tropic of Capricorn, and close to Equatorial. Since the area located close to Equatorial, the climate condition is perfect to grow coffee. That is why countries who produce coffee in the world are mostly laid on this “Coffee Belt” area.
There may be a few different interpretation is going around of what single origin is exactly, but I like to refer to is as coffee that comes from a single known geographical origin and more specifically, a single farm.