Sealed Map: right-click breaks the seal. It turns into a real treasure map with an X – to the nearest undiscovered structure of its kind (otherwise the nearest one).
Found in chests and sold by the innkeeper (emeralds + compass).
Explorer's Compass: sneak + right-click picks the target, right-click searches (every 15 s). The needle then points there; the action bar shows distance and coordinates.
In the Nether and the End it only knows the places of that world.
Crafting Table3 × 3
1 × Explorer's CompassRequired materials
Gold Ingot3 ×Compass1 ×Empty Map1 ×