Sometimes we feel annoyed if our notebook or computer is always used by our friend, so that we can't use it as we want, if we want,we can block some site to access it from our computer, so if you want, you can do this
1.type at run C:\windows\System32\Drivers\etc or you can access from your C: drive
but this way is simple way
2.open the file named hosts with notepad

3.then Under IP 127.0.0.1 localhost add the name of websites you want to block
for example:
127.0.0.1 localhost
127.0.0.2 www.facebook.com
127.0.0.3 www.ringt.com
127.0.0.4 www.blabla.com

finish and that site will no longer be accessable.

Notice: If you can not find the file named Host in the folder of System32, so you can
find it use the search facility in windows.
The thing to remember here is, the more websites that we want to block the tip
of
IP must sequentially, starting from 1 up to how many sites will be blocked.

example:
127.0.0.1 localhost
127.0.0.2 www.hahaa.com
127.0.0.3 www.ringt.com
127.0.0.4 www.blabla.com
127.0.0.5 www.jiji.com
and so on....