How does Paypal works?
When paying for first time via Paypal, you'll be prompted to enter your credit card (or debit card) information, and you'll be able to create your own Paypal account. By doing this, you'll be linking your new Paypal account with your credit card, so you'll be able to pay from now on almost every other online service without entering your private credit card information again.
Since you'll have your own Paypal account, you'll be able to manage all your payments, review all your operations, access the complete help system and customer helpdesk at Paypal. Paypal even allows you to receive money from other people.