But if you do authorize it on your parents' computer in order to either buy some books or to take advantage of your credit at Sony Connect store, remember that it is one of a limited number (I can't remember how many currently) authorized installations, so if you plan on using other computers also take PilotBob's advice on de-authorizing your parents' computer.
They do this because the connect software allows you to read the books right on the computer screen, so you can buy books without ever have a Sony Reader at all, if you enjoy reading books on your computer screen (notebook computers might not be so bad in a pinch). So don't install the connect software, authorize it and then forget about it.
Enjoy the reader and any books you buy! And remember all the fantastic free books you can download from this site, and you could use the unauthorized Connect software to load the free books to the reader.