Outer Terra is the land in which TaskMaker is set. It is home to all the villages, dungeons, and caves which will be visited within the game, along with various "extra" places to explore.
Outer Terra is also the only section of the game to feature no NPCs.
There are a few items of treasure in Outer Terra. There are three gold bars near the top of the map but you will need a ship or remote grasp to get them. There is also a treasure item buried in the sand northeast of Panormous. You will need a shovel to unearth it. The correct square is easiest to find using Magic Map.