What is the coin supply?

Circulating supply
This is the number of coins or tokens that's been mined or generated. It's the number of coins that's currently in public hands and circulating in the market. 

Non-circulating supply
Non-circulating supply is the number of coins that isn't available to the public. For example, coins that are burned or in the hands of the project team. 

Total Supply
This is the number of coins and tokens that currently exist. This is calculated by taking the total number of coins already mined and subtracting that from the total coins burned or destroyed. 

Maximum Supply
Maximum supply includes tokens that have been issued and those that have yet to be issued. For instance, the maximum supply of Bitcoin is 21 million coins. This means that there will only ever be 21 million BTC and no more. No new coins will be produced.