Blocking certain web sites?

How do I block certain sites, www.facebook.con for an example.

Thanks in advance.

Hi, check the link below for the steps.

http://www.wdc.com/wdproducts/library/UM/ENG/4779-705074.pdf#page=70

Page number would be nice.

Page number is imbedded in the URL provided… PDF page 70; document page 65.

It just starts on page 1 for me! Must be the ipad thing. Thanks for the reply.