There are several ways available in order to prevent anyone from accessing any website from your computer system or network.
I am going to be sharing with you this simple technique to prevent any website you dimmed unsave to your computer system or network.
Blocking Unsave Websites Using hosts File
Visit www.infobaseng.com to see how.

Read full details and similar techniques athttp://www.infobaseng.com/can-a-website-be-blocked-technically/