PayPal is a safe and easy way to make payments online. With PayPal you can pay for services online without exposing your credit card number. It is also a much faster way to pay. Just fill in your PayPal username and password and accept the payment.
If you plan to set up an online business, you should consider offering your clients the possibility to pay you via PayPal. Since many affiliate networks also pay out commissions via PayPal, the PayPal account often get a very central role in an online business.
Then it is only natural that many online businesses also prefer to pay their web hosting account with PayPal. You receive payments online into your PayPal account and you use your PayPal funds to pay your web hosting account.