Definition of ball in penalty area vs out of bounds

The PA starts at the General Area side of the line. A ball touches that infinitely thin line it is in the PA. The painted line is in the PA.

The edge of a penalty area extends both up above the ground and down below the ground:
This means that all ground and anything else (such as any natural or artificial object) inside the edge is part of the penalty area, whether on, above or below the surface of the ground.