What to read before developing a service that uses cartography?

Question

Google Maps

I decided to make my own lunar module - with maps and coordinates) The service will be simple, the experience with the Yandex and Google maps API is small, but there is.
While I'm reading articles on Habré and API documentation, I would like to read other resources or interesting articles on this topic.

Answer 1

Learn about free mapping libraries that impose significantly fewer restrictions on use. For example , leafletjs.com/ or openlayers.org/ At the same time, learn about www.openstreetmap.org/
maps .