The worlds were divided into four realms in which they existed.
First was the Mortal Realm, which as the name suggested, would consist of worlds with beings that were mortal and the chances of them being able to cultivate were quite hard.
And here, the simplest kind of natural energy was present enough to let the human beings present her to start their journey on the path of cultivation with great efforts and pains.
The second was the Lesser heavens, where there was a tremendous amount of Spiritual Qi in the worlds present here and there was also a lot of Spiritual Energy which would help in cultivating the realm of Immortal.
As for the Lesser Heavens, there were worlds which had a high quality of Spiritual Energy and also the concentration of it was far denser in the worlds of this plane.
The Lesser and Greater Heavens were collectively called Heavens and people living here would have an abundant age even if they were not a cultivator.
