In short: an online resource for coin collectors. It provides a list of countries and provinces which produce or have produced coins; information about the coins themselves such as their characteristics, history, valuations etc. There will also be a platform to manage your collection/s, track your purchases and share information with others.
To get a general idea of the information part, you can browse the New Zealand pre-decimal coins, for example this page.
The site needs your help! The long-term vision for this site is for it to be a community project. A community of people to do research, publish and verify data, share their collections and generally make the whole thing work.