Nebula in Latin is means fog. Nebula is celestial body that almost like lump of cloud that consists of gas and dust, found between the stars.
In universe is many found the spreading of nebula or fog. Fog in universe can be grouped into two kinds:
1. Milky way nebula, it is called like that because that nebula lies in Milky Way galaxy.
2. Outer Galactic Nebula, that is nebulas that exist beyond Milky Way, but that nebula is not equal to gas fog and dust fog that is found in Milky Way. That nebula consists of billions of stars, then it is called the outer galaxy.