What is the difference between "Circulating Supply", "Total Supply", and "Max Supply"?

Circulating Supply is the best approximation of the number of coins that are circulating in the market and in the general public's hands.
Total Supply is the total amount of coins in existence right now (minus any coins that have been verifiably burned).
Max Supply the best approximation of the maximum amount of coins that will ever exist in the lifetime of the cryptocurrency.