The Dreamlands are a mystic realm can be reached by those in a dreaming state. It should be noted that Dreamers may be able to travel to many other realms, and this should not be regarded as "The Dreaming" or the land of dreams--it is simply a specific realm that can be reached via dreams.
OOC Note Edit
While the Dreamlands are heavily inspired by the mythos of H. P. Lovecraft, Lovecraft's work is not considered explicitly canon to the game--as such, they are not technically those Dreamlands, even though they may bear a striking resemblance in some respects.
Logs featuring Dreamlands: