How does PayPal work?

[WarLocke]

You're better off going to the post office and making out a money order. It's less than a buck if the MO's under $100.

Maybe, but isn't the point of buying over the internet speed? Instead of going to the PO, mailing the money order off, waiting for it to get wherever, and waiting for my goods to get mailed, I just browse over, clicky-click, and the goods get sent off right then and there...

Is the whole PayPal fraud thing ver common?