I could have done it by editing the hosts file. This file is just a plain text file that lives on your computer. It has entries that kind of look like:
127.0.0.1 www.facebook.comSo when a user would surf to a site, Microsoft Windows automatically checks to see if the address is located in the Hosts file. The number shown, 127.0.0.1, is the "loop back" IP address of your own computer, so when the PC looks for facebook.com Windows skips the link to the site (facebook) and moves on. So it can't load any programs, spyware, html anything on that domain.
The Host file can be editied with Notepad so browse for the file, e.g. Windows XP, the file is located in the C:\Windows\System32\Drivers\Etc folder, open it it with notepad and add any sites you want to block by typing 127.0.0.1
would block facebook.com.