Ever wondered what you call these windows?
oriel (noun) – also oriel window or bay window. Window in an upper story (not on the ground floor) that pushes out from the building
(From the French: or = light.)
He was reading a book sitting in the oriel window.
They were standing in the oriel window, taking in the magnificent view over the surrounding park.
Here’s another picture from the inside of a building:
Beautiful, isn’t it?
The reason windows were/are built this way is of course to allow more light to shine in.