Emerald Dream

The Emerald Dream (also known as the Dream of Creation, Green Dream or simply the Dream) is an ethereal, vast, ever-changing world of spirits and untamed nature, that exists outside the boundaries of the physical world, and is the verdant realm of the Dragon Aspect Ysera. As the Emerald Dream is a realm of life, its mirror representing death is the Shadowlands.

The Emerald Dream is basically how the world would have been, if intelligent beings had not altered Azeroth's surface.