Explain the light switch plan drawing

Hello friends,
what do these symbols mean?
The front door opens to the left, the symbols are on the right.
What is meant by this?

Do I understand it correctly,
Top symbols light switch stairwell/hall upstairs.
Middle switch light switch hallway/corridor
Bottom switch for outside light

Please advise

Two "flags" means two-way switching, one is a normal switch

what does that mean now?

Wikipedia explains the two-way switch very well... Nothing more can be deduced from the symbol, i.e. which lamp is controlled by which switch should have been noted or remembered by the electrician.

But they are lamps, right?