PayPal is a payment system for online billing where virtual money is transferred. In this system, the buyer and merchant have an account with PayPal. The account of the buyer is managed by transfers from his own checking account as a credit account, or when depositing the credit card account as a credit account.
In the case of transfers, PayPal retrieves amounts due from this account and transfers them to the merchant's account. The money transfer from the merchant's account to the merchant's checking account is again done by wire transfers.
PayPal makes its appearance during the payment process by displaying a window from PayPal in which the online customer enters his PayPal account details. The transcation is confirmed to the customer by PayPal, at the same time PayPal gives feedback to the online store, which can use this feedback to transfer the goods or services. An alternative for payment on the Internet is the virtual currency Bitcoin.