block any website

block any website :

this is link of file , by editing this file u can block any website.
C:\Windows\System32\drivers\etc\hosts
you can't directly open this page. firstly , open notepad by 'run as administrator' 

then edit the file .
127.0.0.1  local host 
127.0.0.1 www .facebook.com 
{you can write any website name}