You might expect houses in different countries and different climates to be built differently, with sometimes striking dissimilarities.
Notice this difference in a modern Cambodia bathroom. There is an aperture in the wall and half of it is glass brick. That is to let some light into a closed room when there is no power. Or when the homeowner doesn’t turn on the electricity because it’s so expensive.
The other half of the aperture has ventilation bricks installed, to let air circulate through this room and the rest of the house for cooling.
This particular aperture opens into an inside corridor, over the stairway coming up from the first floor.