The card itself functions pretty much like any debit card. Maestro https://onlinecasinopoint.nl/maestro-casino/ is tied to your current account and in certain cases can be a prepaid card. You will enter the card number in the online casino, your card issuer (usually your bank) will authorise the payment if there are funds in your account and this will be visible in your account straight away.
Credit and debit cards are pretty easy to use, are reliable and have become a habit for most. The trouble is that nowadays casinos may reject transactions even if you have sufficient funds in your current account, particularly for players from the United States of America. You will also find casinos that will not accept Maestro. Still, this still seems to be one of the most preferred ways of payments online. With Maestro you can stay safe in the knowledge that a company like MasterCard is providing your transactions.