Your Maestro card is linked to your bank account, and the amount of your purchases is deducted directly from that account. Generally, you enter your PIN on a keypad when you want to purchase an item with Maestro.*
A credit card allows you to pay via instalments and/or a revolving line of credit, with the limit set by the issuer. Your monthly payment can range from a minimum amount, set by your bank, to your entire outstanding balance. Generally, if you pay the entire bill at the end of the month, no interest is charged. If a balance is outstanding, you will be charged interest at a predetermined annual percentage rate (APR), which differs from issuer to issuer.
*Currently, in some countries you may be requested to sign a receipt to complete your Maestro transaction rather than enter your PIN.