BLOCK WEBSITES WITHOUT ANY SOFTWARE

Go to C:\Windows\System32\Drivers\Etc
Find the File named "HOSTS"
Open the said file with the help of Notepad
Under "127.0.0.1 localhost" just add the site you want to block
e.g.
127.0.0.2 www.orkut.com 
127.0.0.3 www.santabanta.com


Save the file & exit notepad. (Restart your computer for changes.)
Now both website are blocked at all.
Just add anyother website you want to block but remember last number must increase in every website.
e.g.
127.0.0.1 localhost
127.0.0.2 www.orkut.com
127.0.0.3 www.santabanta.com
127.0.0.4 www.google.com
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