Help - what is this called? Electronic locks for bathrooms?

[kinshasa]

Thank you Norrbotten, I need to google a bit to get an overview there.

 

[Demmpa]

I also don't want the bathroom directly against the bedroom (or against the kitchen). But apparently, it is modern or American or both.

My brother-in-law has it in their house, the house is from around the 1940s, some house manufacturers have/had it as standard in one/some models for about 20 years ago.

 

[hobbyhenen]

A small LED connected to the lighting that should also have a timer. If the LED is on outside, it is occupied.