Visibility graph
A graph whose nodes are obstacle corners and whose edges join corners that can see each other — the shortest path through it is the shortest path past the obstacles.
Introduced by Tomás Lozano-Pérez and Michael Wesley in 1979 for robot motion planning. Because a shortest path in a plane full of polygonal obstacles always runs straight between obstacle corners, it is enough to build the graph from those corners and run A* or Dijkstra over it.
The path hugs the corners tightly, which looks natural but may need a margin so units don't scrape the wall. In complex 3D, navmesh has largely taken over, but in 2D the visibility graph lives on.