If you wanna block Facebook then modify the host file is vary easy and cool tricks.Because block fb using software is little frustrating .
in window and other operating system use there mini-name server for themselves so that they check their own dns record(domain name server is like converting the domain name (example : Google) into there respected ip address)before asking a name server on the internet.
What is Hosts file
- The hosts file is a simple list of host names and their corresponding IP addresses
- your computer looks at every time you try and contact a previously unknown host name
- If it finds an entry for the computer you're trying to reach, it sets the IP address for that computer to be whatever in the hosts file.
Also Check: Important Shortcut key