This website is based on Nominatim UI, a debugging interface for the Nominatim geocoding software.
The Nominatim API is installed at Nominatim_API_Endpoint and for questions you
should contact their administrators.
Nominatim is a search engine for OpenStreetMap data. You may search for a name or address (forward search) or look up data by its geographic coordinate (reverse search). Each result comes with a link to a details page where you can inspect what data about the object is saved in the database and investigate how the address of the object has been computed.
If you're the administrator of this website you can edit the text above in
dist/theme/about-and-help.html