Question from a non-jew. Found on the door frame of an apartment in Hungary. What is it?

Hello, first time coming to this sub. Wasn’t sure where to ask so I came here. I found this on the right side of the doorframe of a family member in Hungary. What is it? Can someone explain to me?

I have read about Judaism and learned some Hebrew. Especially since I come from a part of the world where Judaism was/is prominent, so curious to know more. Thank you.